About This Document

[ ]

items in brackets are optional

{ }

curly braces enclose items you choose from

|

the vertical bar separates choices in curly braces

normal monospace

normal monospace text in syntax specifications should be typed in exactly as presented. Because UNIX and variants are case-sensitive, case must be preserved. Monospace is also used in presenting items that appear on the screen.

monospace italics

italics in syntax specifications indicate items that are to be replaced with an actual item (e.g. interface should be replaced with an actual interface name, like eth0.

• Total, IP, TCP, UDP, ICMP, and non-IP byte counts
• TCP source and destination addresses and ports
• TCP packet and byte counts
• TCP flag statuses
• UDP source and destination information
• ICMP type information
• OSPF source and destination information
• TCP and UDP service statistics
• Interface packet counts
• Interface IP checksum error counts
• Interface activity indicators
• LAN station statistics

IPTraf can be used to monitor the load on an IP network, the most used types of network services, the proceedings of TCP connections, and others.

IPTraf is software-only, and utilizes the built-in raw packet capture interface of the Linux kernel, allowing it to be used with a wide range of Ethernet cards, supported FDDI adapters, supported ISDN adapters, and any asynchronous SLIP/PPP interface. No special hardware is required.

System Requirements

• 80386 or later. i486DX2-75 MHz or later (or equivalents) will give better performance. Faster machines reduce the chances of missed packets. Pentium-class (Pentium, PPro, PII, PIII) or compatible (K6, 6x86, MII) machines are recommended.

  ---

  Note Other architectures (SPARC, Alpha, M68K, PowerPC, etc) may also be used but no tests have been performed on them. Distribution-specific packages may be available, check with the package maintainer for details

  ---

• Linux 2.2.0 or later.

  ---

  Note If you're running a custom-built kernel, make sure you compile in or install as a module the Packet Socket kernel option, or IPTraf (and others like it) will fail.

  ---

• 8MB of physical RAM or higher. More recommended. 16MB virtual memory or more recommended (physical memory + swap space)
• Shared C library 5. The precompiled binary does not require the shared ncurses libraries (yet), as they are linked in. You can recompile if you'd like to use your shared ncurses and panels libraries.
• Terminfo database in /usr/share/terminfo
• Console or high-speed terminal
• Ethernet, FDDI, ISDN, PLIP, or asynchronous SLIP/PPP interfaces

• tar
• GNU zip (gzip)

If you downloaded IPTraf from the Internet, follow these steps to install the software:

1. Decompress the .tar.gz file by entering
   tar zxvf iptraf-x.y.z.tar.gz

   If your tar doesn't support the z option, you can separately decompress the tar.gz then extract the resulting .tar archive.

   gunzip iptraf-x.y.z.tar.gz
   tar xvf iptraf-x.y.z.tar
   

   This will decompress the sources into a directory called iptraf-x.y.z.
   (x.y.z here should be the IPTraf version number you're installing, like 2.4.0).

2. Change to the iptraf-x.y.z top level directory.
3. To install the software, run the Setup program by entering
   ./Setup

   while you are logged in as root. This will install the distribution binary in the /usr/local/bin directory. All needed directories will also be created.

1. Insert the floppy in the drive.
2. Mount the floppy on an empty directory. For example, to mount the floppy in the first floppy drive under a directory called /mnt, enter
   mount -t ext2 /dev/fd0 /mnt

   This assumes your floppy is in /dev/fd0. You can use any empty directory in place of /mnt. With most Linux installations, this will work fine.

3. After mounting, change to the /mnt (or whatever) directory.
4. Enter
   ./Setup

   while logged in as root.

This will copy the binaries to /usr/local/bin, and create the necessary working directories.

5. Unmount the diskette by typing
   umount /mnt

   (That's umount, not unmount.) You can then eject the diskette. Store it in a safe place.

You will also be asked if you want to view the RELEASE-NOTES file. It is recommended that you do so at that point.

In both cases (downloaded and floppy), the installation will store the program in /usr/local/bin with the binaries owned by user root, readable, writable, and executable by the owner, no permissions for the group, no permissions for all others. (700 octal, or -rwx------).

There have been no file format changes since version 1.4. If you're upgrading from a version prior to 1.4, do the "make upgrade" procedures from each semi-major version in sequence (e.g. 1.2 -> 1.3 -> 1.4).

iptraf

at the shell prompt. You will see a copyright notice, with an instruction to press any key to get started. Just press any character key, and you will be immediately taken to the main menu. All major functions of the program are found here.

Entering the IPTraf command without any command-line parameters brings up the program's main menu. From there, you can select the facilities you want.

IPTraf determines and makes use of the maximum number of lines and columns on the terminal.

TERMINFO=/usr/lib/terminfo
export TERMINFO

You can place these commands in your ~/.profile or the systemwide /etc/profile startup files.

You can also create a symbolic link named /usr/share/terminfo to let it point to your existing terminfo (assuming again your terminfo is in /usr/lib/terminfo):

ln -s /usr/lib/terminfo /usr/share/terminfo

Or you can recompile your program to use your existing ncurses library installation. If you do this, make sure you have ncurses 1.9.9e or later.

The following command-line parameters can be supplied to the iptraf command:

General Information

A number standing alone with no suffix represents an exact count. A number with a K following is a kilo (thousand) figure. An M, G, and T suffix represents mega (million), giga (billion), and tera (trillion) respectively. For example

1024067	exactly 1024067
1024K	approximately 1024000
1024M	approximately 1024000000
1024G	approximately 1024000000000
1024T	approximately 1024000000000000

These notations apply to both packet and byte counts.

lo

The loopback interface. Every machine has one, and has an IP address of 127.0.0.1. lo is also indicated if data is detected on the dummyn interface(s).

ethn

An Ethernet interface. n starts from 0. Therefore, eth0 refers to the first Ethernet interface, eth1 to the second, and so on. Most machines only have one.

fddin

An FDDI interface. n starts from 0.

pppn

A PPP interface. n starts from 0. Therefore, ppp0 is the first PPP interface, ppp1 is the second, and so on.

slin

A SLIP interface. n starts from 0. Same sequence as above

ipppn

A synchronous PPP interface using ISDN. n starts from 0.

isdnn

ISDN interfaces can be given arbitrary names, but for them to work with IPTraf, they must be named isdnn. IPTraf supports synchronous PPP (the ipppn interfaces above), raw IP, and Cisco-HDLC encapsulation.

plipn

PLIP interfaces. These are point-to-point IP connections using the PC parallel port.

Your system's network interfaces must be named according to the schemes specified above.

There are two windows in the Traffic Monitor. Both of them can be scrolled with the Up and Down cursor keys. Just press W to move the Active indicator to the window you want to control.

• Source address and port
• Packet count
• Byte count
• Source MAC address
• Packet Size
• Window Size
• TCP flag statuses
• Interface

The TCP window is scrollable, and you can use the Up and Down arrow keys on your keyboard to view more connections when the TCP window is marked Active.

Because this monitoring system relies solely on packet information, it does not determine which endpoint initiated the connection. In other words, it does not determine which endpoint is the client, and which is the server. This is necessary because it can operate in promiscuous mode, and as such cannot determine the socket statuses for other machines on the LAN.

That being the case, the system displays two entries for each connection, one for each direction of the TCP connection. To make it easier to determine the direction pairs of each connection, a bracket is used to "join" both together. This bracket appears at the leftmost part of each entry.

Just because a host entry appears at the upper end of a connection bracket doesn't mean it was the initiator of the connection.

Each entry in the window contains these fields:

Source address and port
The source address and port indicator is in address:port format. This indicates the source machine and TCP port on that machine from which this data is coming.

The destination is the host:port at the other end of the bracket.

Packet count
The number of packets received for this direction of the TCP connection

Byte count
The number of bytes received for this direction of the TCP connection. These bytes include total IP and TCP header information, in addition to the actual data. Data link header (e.g. Ethernet and FDDI) data are not included.

Source MAC address
The address of the host on your local LAN that delivered this packet. This can be viewed by pressing M once if Source MAC addrs in traffic monitor is enabled in the Configure menu.

Packet Size
The size of the most recently received packet. This item is visible if you press M for more TCP information. This is the size of the IP datagram only, not including the data link header.

Window Size
The advertised window size of the most recently received packet. This item is visible if you press M for more TCP information.

Flag statuses
The flags of the most recently received packet.

S

SYN. A synchronization is taking place in preparation for connection establishment. If only an S is present (S---) the source is trying to initiate a connection. If an A is also present (S-A-), this is an acknowledgment of a previous connection request, and is responding.

A

ACK. This is an acknowledgment of a previously received packet

P

PSH. A request to push all data to the top of the receiving queue

U

URG. This packet contains urgent data

RESET

RST. The source machine indicated in this direction reset the entire connection. The direction entries for reset connections become available for new connections.

DONE

The connection is done sending data in this direction, and has sent a FIN (finished) packet, but has not yet been acknowledged by the other host.

CLOSED

The FIN has been acknowledged by the other host. When both directions of a connection are marked CLOSED, the entries they occupy become available for new connection entries.

-

The flag is not set

• User Datagram Protocol (UDP)
• Internet Control Message Protocol (ICMP)
• Open Shortest-Path First (OSPF)
• Interior Gateway Routing Protocol (IGRP)
• Interior Gateway Protocol (IGP)
• Internet Group Management Protocol (IGMP)
• General Routing Encapsulation (GRE)
• Address Resolution Protocol (ARP)
• Reverse Address Resolution Protocol (RARP)

Unrecognized IP packets are indicated by their protocol numbers while non-IP packets are indicated as Non-IP in the lower window.

Well, strictly speaking, ARP and RARP packets aren't IP packets, since they are not encapsulated in an IP datagram. They're just indicated because they are integral to proper IP operation on LANs.

For all packets in the lower window, only the first IP fragment is indicated (since that contains the header of the IP-encapsulated protocol) but with no further information from the encapsulated protocol.

UDP packets are also displayed in address:port format. ICMP entries also contain the ICMP message type. For easier location, each type of protocol is color-coded (text console only).

UDP	Red on White
ICMP	Yellow on Blue
OSPF	Black on Cyan
IGRP	Bright white on Cyan
IGP	Red on Cyan
IGMP	Bright green on Blue
GRE	Blue on White
ARP	Bright white on Red
RARP	Bright white on Red
Other IP	Yellow on Red
Non-IP	Yellow on Red

The lower window can hold up to 512 entries. You can scroll the lower window by using the W key to move the Active indicator to it, and by using the Up and Down cursor keys. The lower window automatically scrolls every time a new entry is added, and either the first entry or last entry is visible. Upon reaching 512 entries, old entries are thrown out as new entries are added.

Some entries may be too long to completely fit in a screen line. You can use the Left and Right cursor keys to vertically scroll the lower window when it is marked Active.

Entries for packets received on LAN interfaces also include the source MAC address of the LAN host which delivered it. This behavior is enabled by turning on the Source MAC addrs in traffic monitor toggle in the Configure menu.

Entry Details
In general, the entries in the lower window indicate the protocol, the IP datagram size (full frame size for non-IP, including ARP and RARP), the source address, the destination address, and the network interface the packet was detected on. However, some protocols have a little more information.

ICMP: ICMP entries are displayed in this format:

ICMP type (subtype) (size bytes) from source to destination [(src HWaddr srcMACaddress)] on interface

where type could be any of the following:

echo req, echo rply

ICMP echo request and reply. Usually used by the ping program and other network monitoring and diagnostic program.

dest unrch

ICMP destination unreachable. Something failed to reach its target. The dest unreach type is supplemented with a further indicator of the problem. Destination unreachable messages for TCP traffic causes the corresponsing TCP entry in the upper window to be made available for reuse by new connections.

redirct

ICMP redirect. Usually generated by a router to tell a host that a better gateway is available.

src qnch

The ICMP source quench is used to stop a host from transmitting. It's some kind of flow control mechanism.

time excd

Indicates a packet's time-to-live value expired before it got to its destination. Mostly happens if a destination is too far away. Also used by the traceroute program.

router adv

ICMP router advertisement

router sol

ICMP router solicitation

timestmp req

ICMP timestamp request

timestmp rep

ICMP timestamp reply

info req

ICMP information request

info rep

ICMP infromation reply

addr mask req

ICMP address mask request

addr mask rep

ICMP address mask reply

param prob

ICMP parameter problem

bad/unknown

An unrecognized ICMP packet was received, or the packet is corrupted.

The destination unreachable message also includes information on the type of error encountered. Here are the destination unreachable codes:

ntwk

network unreachable

host

host unreachable

proto

protocol unreachable

port

port unreachable

pkt fltrd

packet filtered (normally by an access rule on a router or firewall)

DF set

the packet has to be fragmented somewhere, but its don't fragment (DF) bit is set.

src rte fail

source route failed

src isltd

source isolated (obsolete)

net comm denied

network communication denied

host comm denied

host communication denied

net unrch for TOS

network unreachable for specified IP type-of-service

host unrch for TOS

host unreachable for specified IP type-of-service

prec violtn

precedence violation

prec cutoff

precedence cutoff

dest net unkn

destination network unknown

dest host unkn

destination network unknown

For more information on ICMP, see RFC 792.

OSPF: OSPF messages also include a little more information. The format of an OSPF message in the window is:

OSPF type (a=area r=router) (size bytes) from source to destination [(src HWaddr srcMACaddress)] on interface

The type can be one of the following:

hlo

OSPF hello. Hello messages establish OSPF communications and keep routers informed of each other's presence.

DB desc

OSPF Database Description

LSR

OSPF Link State Request

LSU

OSPF Link State Update. Messages indicating the states of the OSPF network links

LSA

OSPF Link State Acknowledgment

The entries in parentheses:

a=area

The area number of the OSPF message

r=router

The IP address of the router that generated the message. It is not necessarily the same as the source address of the encapsulating IP packet.

Many times, the destination addresses for OSPF packets are class D multicast addresses in standard dotted decimal notation or (if reverse lookup is enabled), hosts under the MCAST.NET domain. Such multicast addresses are defined as follows:

224.0.0.5 (OSPF-ALL.MCAST.NET)

OSPF all routers

224.0.0.6 (OSPF-DSIG.MCAST.NET)

OSPF all designated routers

See RFC 1247 for details on the OSPF protocol.

With logging enabled, the IP Traffic Monitor prompts you for a log file name. The default name is ip_traffic-n.log (where n is what instance of the traffic monitor this is (1, 2, 3, and so on). (e.g. if this is the first instance, the default file name will be ip_traffic-1.log.)

At any time, you can press X or Q to return to the main menu (or back to the shell if the monitor was started with iptraf -i).

The activity indicators can be toggled between kbits/s and kbytes/s with the Activity mode configuration option.

The general statistics window will dynamically add new entries as packets from newly-created interfaces (e.g. new PPP interfaces) are intercepted. Long lists can be scrolled with the Up, Down, PgUp, and PgDn keys.

Copies of the statistics are written to the log file iface_stats_general.log at regular intervals if logging is enabled. See the Logging option below.

This facility can be started directly from the command line with the -g option to the iptraf command.

• IP packet and byte counts
• TCP packet and byte counts
• UDP packet and byte count
• ICMP packet and byte counts
• Other IP-type packet and byte counts
• Non-IP packet and byte counts
• Checksum error count
• Interface activity

All IP byte counts (IP, TCP, UDP, ICMP, other IP) include IP header data and payload. The data link header is not included. The full frame length (including data-link header) is included in the non-IP and Total byte count.

The upper portion of the screen contains the packet and byte counts for all IP and non-IP packets intercepted on the interface. The lower portion contains the total, incoming, and outgoing interface data rates.

This facility also displays incoming and outgoing counts and data rates. The packet size breakdown in versions prior to 2.0.0 has been moved to its own facility under Statistical breakdowns/By packet size.

An outgoing packet is one that exits your interface, regardless of whether it originated from your machine or came from another machine and was routed through yours. An incoming packet is one that enters your interface, either addressed to you directly, broadcast, multicast, or captured promiscuously.

The rate indicators can be set to display kbits/s or kbytes/s with the Activity mode configuration option.

If you wish to start this facility directly from the command line, you can specify the -d parameter and an interface to monitor. For example,

iptraf -d eth0

starts the statistics for eth0. The interface must be specified, or IPTraf will not start the facility.

The figure for the IP checksum error is a packet count only, because the corrupted IP header cannot be relied upon to give a correct IP packet length value.

The figures are logged at regular intervals if logging is enabled. The default log file name at the prompt is iface_stats_detailed-iface.log where iface is the selected interface for this session (for example, iface_stats_detailed-eth0.log).

Pressing X or Q takes you back to the main menu (if this facility was started with the command-line option, X or Q drops you back to the shell).

Statistical Breakdown: Packet Sizes

The packet size breakdown takes the interface's Maximum Transmission Unit (MTU) size and divides it into 20 brackets, each bracket containing a range of sizes. As a packet is captured, its size is determined and the appropriate bracket is incremented.

This facility provides an idea as to the packet sizes passing over your network, and can aid in network (re)design decisions.

If logging is enabled, copies of the statistics are written at regular intervals to a log file. The default log file name is packet_size-iface.log where iface is the selected interface for this session (for example, packet_size-eth0.log).

The packet size breakdown can also be invoked straight from the command line by specifying the -z iface parameter. The interface parameter is required. For example, this command runs the facility on interface eth0.

iptraf -z eth0

To exit, press X or Ctrl+X.

The statistics window indicates the protocol (TCP or UDP), the port number, the total packets and bytes counted for this particular protocol/port combination, the packets and bytes destined for that protocol and port, and the packets and bytes coming from that protocol and port.

Byte counts include the IP header and payload only. The data link header is not included.

The protocol/port indicators are color-coded for easier identification. TCP indicators are in yellow, UDP in bright green (TCP is normal, UDP is bold white in non-color mode).

Some network applications or protocols may use port numbers higher than 1023. Examples of these include application proxy servers (HTTP proxy servers typically use values like 8000, 8080, 8888, and the like), and IRC (IRC servers commonly accept connections on ports 6660 to 6669). These ports are by default not included in the counts. If you do want to include a higher-numbered port in the statistics, you can add them yourself from the Configure/Additional port... menu item. See the section below.

If logging is enabled, The statistics are also written to a log file (the default name is tcp_udp_services-iface.log, where iface is the selected interface (for example, tcp_udp_services-eth0.log).

Sorting TCP/UDP Entries
Pressing the S key brings up a window which allows you to select the field by which the entries will be sorted. You can press R to sort by port, P to sort by total packets, B to sort by total bytes, T to sort by incoming packets (To packets), O to sort by incoming bytes (To bytes), F to sort by outgoing packets (From packets) and M to sort by outgoing bytes (Fom bytes). Pressing any other key cancels the sort.

Port numbers are sorted in ascending order (least first) but statistics are sorted in descending order (largest counts first).

As with the IP Traffic Monitor, sorting is performed only with this sequence. Automatic sorting is not performed so as not to affect performance.

If you wish to start this facility from the command line, you can use the -s option followed by an interface to monitor. For example,

iptraf -s eth0

brings up this module for traffic on eth0. The interface must be specified, or IPTraf will drop back to the shell.

The entry above each line of statistics is the station's LAN type (Ethernet, PLIP, or FDDI) and the hardware MAC address. Each statistics line consists of the following information:

• Total packets incoming
• IP packets incoming
• Total bytes incoming
• Incoming rate
• Total packets outgoing
• IP packets outgoing
• Total bytes outgoing
• Outgoing rate

The byte counts include the data link header. The activity indicators can be set to display kbits/s or kbytes/s with the Activity mode configuration option.

This facility works only for Ethernet, PLIP, and FDDI frames. Loopback. ISDN, and SLIP/PPP networks are not monitored here.

Copies of the statistics are written to a log file at regular intervals if logging is enabled. The default log file name is lan_statistics-n.log, where n is the instance number of this facility (for example, if this is the first instance, the generated default log file name is lan_statistics-1.log).

Sorting the LAN Station Monitor Entries
Press S to sort the entries. A box will pop up and display the keys you can press to select the field by which the entries will be sorted. Press P to sort by total incoming packets, I to sort by incoming IP packets, B to sort by total incoming bytes, K to sort by total outgoing packets, O to sort by outgoing IP packets, and Y to sort by total outgoing bytes. Pressing any other key cancels the sort.

The wildcard mask also does not have to end on a byte boundary; you may mask right into a byte itself. For example, 255.255.255.224 masks 27 bits (224 is 11100000 in binary).

Leaving the wildcard mask fields blank or storing invalid data in them causes the filter to recognize the entries as 255.255.255.255.

IPTraf also accepts host names in place of the IP addresses. IPTraf will resolve the host name when the filter is loaded. When the filter is interpreted, the wildcard mask will also be applied. This can be useful in cases where a single host name may resolve to several IP addresses.

The Port field should contain a port number of the service you may be interested in. Leave it at 0 to let the filter ignore it. You will most likely be interested in target ports rather than source ports (which are usually unpredictable anyway, perhaps with the exception of FTP data).

Fill out the second set of fields with the parameters of the opposite end of the connection. As previously mentioned, you may place either set of parameters in either set. By default, the second set of parameters are preset to 0.0.0.0, 0.0.0.0, 0. Just Backspace or Delete over them and replace them if needed.

The last field is marked Include/Exclude. This field allows you to decide whether to include or exclude this entry from the display. Setting this field to I causes the filter to display matching entries, while setting it to E causes the filter to supress the display of matching entries. This field is set to I by default.

Press Enter to accept all parameters when done. The parameters will be accepted and you'll be presented with another blank form. You can enter as many sets of paramters as you wish. Press Ctrl+X at a blank form when done.

Examples
To see all traffic to/from host 202.47.132.1 from/to 207.0.115.44, regardless of TCP port

Host name/IP Address    202.47.132.2            207.0.115.44
Wildcard mask		255.255.255.255		255.255.255.255
Port                    0                       0
Include/Exclude         I

Host name/IP Address    207.0.115.44            202.47.132.0
Wildcard mask		255.255.255.255		255.255.255.0
Port                    0                       0
Include/Exclude         I

Host name/IP Address    0.0.0.0                 0.0.0.0
Wildcard mask		0.0.0.0			0.0.0.0
Port                    80			0
Include/Exclude         I

Host name/IP Address    202.47.132.2            0.0.0.0
Wildcard mask		255.255.255.255		0.0.0.0
Port                    25                      0
Include/Exclude         I

Host name/IP Address	sunsite.unc.edu		cebu.mozcom.com
Wildcard mask		255.255.255.255		255.255.255.255
Port			0			0
Include/Exclude         I

Host name/IP Address    140.66.5.x              0.0.0.0
Wildcard mask           255.255.255.0           0.0.0.0
Port                    0                       0
Include/Exclude         E

You can enter as many parameters as you wish. All of them will be interpreted when the filter is processed.

Excepting Certain Sites from the Display
Filters follow an "implicit no-display" policy, that is, only explicitly defined sites will be displayed, everything else is not. This is similar to the access-list policy "whatever is not explicitly permitted is denied". If you want to show all traffic to/from everywhere, except certain places, you can specify the sites you wish to exclude, mark them with E in the Include/Exclude field, and define a general catch-all entry with source address 0.0.0.0, mask 0.0.0.0, port 0, and destination 0.0.0.0, mask 0.0.0.0, port 0, tagged with an I in the Include/Exclude field as the last entry.

For example:

To see all traffic except all SMTP, Web, and traffic from/to 207.0.115.44:

Host name/IP address            0.0.0.0                 0.0.0.0
Wildcard mask                   0.0.0.0                 0.0.0.0
Port                            25                      0
Include/Exclude                 E

Host name/IP address            0.0.0.0                 0.0.0.0
Wildcard mask                   0.0.0.0                 0.0.0.0
Port                            80                      0
Include/Exclude                 E

Host name/IP address            207.0.115.44            0.0.0.0
Wildcard mask                   255.255.255.255         0.0.0.0
Port                            0                       0
Include/Exclude                 E

Host name/IP address            0.0.0.0                 0.0.0.0
Wildcard mask                   0.0.0.0                 0.0.0.0
Port                            0                       0
Include/Exclude                 I

Toggles

This option is off by default.

TCP/UDP service Names
This option, when on, causes IPTraf to display the TCP/UDP service names (smtp, www, pop3, etc.) instead of their numeric ports (25, 80, 110, etc). The number-to-name mappings will depend on the systems services database file (usually /etc/services). Should there be no corresponding service name for the port number, the numeric form will still be displayed.

This setting is off by default.

Force promiscuous
If this option is enabled, your LAN interfaces will capture all packets on your LAN. Using this option enables you to see all TCP connections and packets passing your LAN segment, even if they're not from or for your machine. When this option is active in the statistics windows, the Activity indicators will show a good estimate of the load on your LAN segment.

When this option is disabled, you'll only receive information about packets coming from and entering your machine.

The setting of this option affects all LAN (both Ethernet and FDDI) interfaces on your machine, if you have more than one.

The interface's promiscuous flag is set only when a facility is started, and turned of when it exits. However, if promiscuous mode was already set when a facility was started, it remains set on exit.

If multiple instances of IPTraf are started, the promiscuous setting is restored only upon exit of the last facility.

Color
Turn this on with color monitors. Turn it off with black-and- white monitors or non-color terminals (like xterms). Changes to this setting will take effect the next time the program is started.

Color is on by default on consoles, off on non-color terminal types like xterms and VT100s.

Logging
When this option is active, IPTraf will log information to a disk file, which can be examined or analyzed later. Starting with IPTraf 2.4.0, IPTraf prompts you for the name of the file to which to write the logs. It will provide a default name, which you are free to accept or change. The IP Traffic Monitor and LAN Station Monitor will generate a log file name that is based on what instance they are (first, second, and so on). The General Interface Statistics' default log file name is constant, because it listens to all interfaces at once, and only one instance can run at one time.

The other facilities generate a log file name based on the interface they're listening on

See the descriptions on the facilities above for the default log file names.

Press Enter to accept the log file name, or Ctrl+X to cancel. Cancelling will turn logging off for that session.

The IP Traffic Monitor will write the following pieces of information to its log file:

• Start of the traffic monitor
• Receipt of the first TCP packet for a connection. If that packet is a SYN, (SYN) will be indicated in the log entry. (Of course, the traffic monitor may start in the middle of established connections. It will still count those packets. This also explains why some connection entries may become idle if the traffic monitor is started in the middle of a half-closed connection, and miss the first FIN. Such entries time out in a while.)
• Receipt of a FIN
• ACK of a FIN
• Timeouts of TCP entries
• Everything that appears in the bottom window of the traffic monitor
• Stopping of the traffic monitor

Each log entry includes the date and time the entry was written. Logging is also affected by the defined filters.

Log files can grow very fast, so be prepared with plenty of free space and delete unneeded logs. Log write errors are not indicated.

Copies of the interface statistics, TCP/UDP statistics, packet size statistics, and LAN host statistics are also written to the log files at regular intervals. See Log Interval... below.

IPTraf closes and reopens the active log file when it receives a USR1 signal. This is useful in cases where a facility is run for long periods of time but the log files have to be cleared or moved.

To clear or move an active log file, rename it first. IPTraf will continue to write to the file despite the new name. Then use the UNIX kill command to send the running IPTraf process a USR1 signal. IPTraf will then close the log file and open another with the original name. You can then safely remove or delete the renamed file.

Do not delete an open log file. Doing so will only result in a file just as large but filled with null characters (ASCII code 0).

Logging comes disabled by default. The USR1 signal is caught only if logging is enabled, it is ignored otherwise.

Activity mode
Toggles activity indicators in the interface and LAN statistics facilities between kilobits per second (kbits/s) or kilobytes per second (kbytes/s).

The default setting is kilobits per second.

Source MAC addrs in traffic monitor
When enabled, the IP traffic monitor retrieves the packets' source MAC addresses if they came in on an Ethernet, FDDI, or PLIP interface. The addresses appear in the lower window for non-TCP packets, while for TCP connections, they can be viewed by pressing M.

No such information is displayed if the network interface doesn't use MAC addresses (such as PPP interfaces).

This can be used to determine the actual source of the packets on your local LAN.

The traffic monitor also logs the MAC addresses with this option enabled. The default setting is off.

Timers

TCP Timeout
This figure determines the amount of time (in minutes) a connection entry may remain idle before it becomes eligible for replacement by a new connection. The default is 15 minutes. You may want to reduce this on an isolated (not connected to the Internet) LAN or a LAN connected to the Internet with high-speed links. Just enter the new value and press Enter. You can press Ctrl+X to leave the current value unchanged.

Log Interval
This figure determines the number of minutes between logging of interface statistics, TCP/UDP figures, and LAN host statistics. The default is 60 minutes. This figure is meaningless if logging is disabled.

Screen Update Interval
This value determines the rate in seconds at which the screen is updated. The default is 0, which means the screen is updated as fast as possible, giving close-to-realtime reflection of network activity. However, this high-speed update can cause incredible amounts of traffic if IPTraf is run on a remote termnial (e.g. a Telnet or Secure Shell session). You can set this to a higher value, such as 1 or 2 seconds to slow down the updates.

This figure does not affect the rate of data capture. Only the screen refresh is affected. The figures are still updated as fast as possible, although the figure display will no longer be as close to realtime.

The default setting is 0, which shouldn't be a problem on the console. Set it to a slightly higher value on remote terminals or slow links. The setting affects all monitoring facilities.

However, since many users like rapid counts on their screen, a compromise was incorporated. Even when the screen update interval is set to 0, there is still a 50ms delay between screen updates (except the LAN station monitor, which has a 100 ms delay). This is still visually fast, but provides more time to the packet capture routine. Higher delays may result in better accuracy of counts and activity.

In any case, this setting only affects screen updates. Capture still proceeds as fast as possible.

TCP closed/idle persistence
This paremeter determines the interval (in minutes) at which the IP Traffic Monitor clears from the TCP display window all closed, idle, and timed out entries. Enter 0 to keep such entries on the screen indefinitely, disappearing only when replaced by new connections.

Custom Information

Additional port
Select this item to enter a port number to be included in the TCP/UDP counts in the TCP/UDP service statistics main menu item described above. By default, port numbers above 1023 are not monitored. If you do have a higher-numbered port to monitor, enter it here.

You will see two fields. If you have only one port to enter, just fill up the first field. To specify a range, fill both fields, the first port in the first field, the last port in the second field.

You can select this option multiple times to add more values or ranges.

Delete port/range
Select this item to remove a higher-numbered port number or port range you entered earlier with the Additional port... option. A window will come up containing the entered ports and ranges. Select the entry you want delete and press Enter.

Selecting the Ethernet/PLIP host descriptions or FDDI host descriptions options brings up a submenu asking you to add, edit, or delete descriptions.

To add a new description, select the Add description... option. A dialog box will appear, asking you for the MAC address and an appropriate description. Type in the address in hexadecimal notation with no punctuation of any kind. The dialog box is case-insensitive for the address; the alphabetical digits A to F will be stored in lowercase.

Use the Tab key to move between fields and Enter to accept. Press Ctrl+X to discard this dialog and return to the main menu.

The description may be anything: the IP address, a fully-qualified domain name, or a description of your liking as long as the field can hold.

Enter as many descriptions as you need. Press Ctrl+X at a blank dialog after you have entered the last entry

These descriptions will be displayed alongside the MAC addresses in the LAN station monitor, together with the type of frame (Ethernet, PLIP, or FDDI).

An existing address or description may be edited by selecting the Edit description... option from the submenu. A panel will appear with a list of existing address descriptions. Select the one you wish to edit and press Enter. A dialog box identical to that when you add a description will appear with prefilled fields. Just backspace over and edit the fields. Press Enter to accept or Ctrl+X to cancel.

Selecting the Delete description... submenu item brings up the selection panel. Select the description you want to delete and press Enter. You can also press Ctrl+X to cancel the operation.

IPTraf 2.4 and later also recognizes the /etc/ethers file. Should a hardware address be present in the IPTraf definition files and in /etc/ethers, the IPTraf definition will be used.

address:description

For example

00201e457e:Cisco 3640 gateway

Do not put colons, periods, or any invalid characters in the MAC address.

Before starting a statistical facility in the background, configure IPTraf in the usual way (set filters, add TCP/UDP ports, etc).

Once that's done, exit all instances of IPTraf on the system, then invoke IPTraf from the command line with the parameter to start the facility you want, the timeout (-t) parameter if you wish, and the -B parameter to actually daemonize the program. For example, to run the IP Traffic Monitor in the background for all interfaces, issue the command

iptraf -i all -B

To run the Detailed Interface Statistics on interface eth0 for 5 minutes in the background:

iptraf -d eth0 -t 5 -B

If the timeout parameter is not specified, the facility will run until the process recieves a USR2 signal. To stop a facility in the background, do a

ps x

at the command line, and find the process id (pid) of the iptraf process you're looking for. Then send that process a USR2 signal with the kill command:

kill -USR2 pid

Since IPTraf cannot send error messages to the terminal, all messages are written to the file daemon.log in the IPTraf logging directory.

The -B automatically enables logging regardless of its configured setting. The parameter is ignored if not used with one of the parameters to start a facility from the command line.

The log file can be specified with the -L command-line parameter. If this parameter is not specified, the default log file name for the facility will be used (see the descriptions of the facilities above for the default log name patterns). If you don't specify an path, the log file will be placed in /var/log/iptraf.

Unable to read config file
The configuration record cannot be read. You most likely have a disk problem.

Unable to write config file
The configuration file cannot be written. You either have a disk problem, or (more likely), your disk is full.

Error loading filter list file
IPTraf cannot access the list of defined TCP or UDP filters. Can also be an indicator of a bad disk.

Error writing filter list file
The filter list file cannot be written to. You may have trouble accessing your filters.

Unable to read filter file
IPTraf cannot read the filter data off the file. Could be caused by a bad disk.

Error opening filter file
IPTraf cannot open the filter file. Could be caused by a shortage of file descriptors or a bad disk.

Unable to write TCP/UDP filter record
IPTraf cannot add the newly defined filter to the filter list.

Cannot create TCP/UDP filter record file
IPTraf cannot create the filter record file. The defined filter is lost.

Unable to create TCP/UDP filter file
IPTraf cannot create the filter data file.

Unable to save TCP/UDP filter name
IPTraf cannot save the name of the current TCP filter. IPTraf will start with no filters active the next time it is invoked.

Unable to save filter changes IPTraf cannot save the changes you made to the filter. You probably have a disk error.

Unable to retrieve saved TCP/UDP filter
The saved filter cannot be retrieved. IPTraf will start with no TCP filters active.

Unable to write non-TCP filters
IPTraf was not able to write the filters for the other protocols. Probably due to a bad disk or full filesystem.

Unable to save interface flags
IPTraf was unable to save the flags of the network interfaces. This is probably due to a bad installation or full filesystem.

Unable to retrieve saved interface flags
IPTraf was unable to retrieve the save interface flags. Probably again due to a bad installation or full filesystem.

protocol data file in use; try again later
Another IPTraf process is modifying the TCP or UDP filter data, and has locked the files. Try again once the other IPTraf process has terminated or completed its modifications and unlocked the files.

Unable to resolve hostname
The indicated host name in the filter cannot be resolved into an IP address. Check the local hosts database /etc/hosts or your machine's DNS configuration or DNS server.

The filter parameters will not be used.

Unable to open host description file
IPTraf cannot open the file containing the descriptions for Ethernet or FDDI addresses. Could be due to a bad disk or a hit on the file descriptor limit.

Unable to write host description
IPTraf was unable to write the description record for this Ethernet or FDDI address. Could be due to a bad disk or corrupted filesystem.

No descriptions
You tried to edit or delete a description with no previous descriptions defined.

Cannot open log file
There is a problem opening the log file. There is most likely a problem with the disk, or there are too many open files.

Unable to obtain interface list
IPTraf was unable to retrieve the list of network interfaces from the /proc filesystem. This may be due to a badly configured kernel. IPTraf needs /proc filesystem support.

Unable to obtain interface parameters for interface
The system call to retrieve the interface's flags failed. Check your interface or kernel driver.

Promisc change failed for interface
The system call to change the promiscuous flag failed. Check your interface or its kernel driver.

Unable to open raw socket for flag change
IPTraf was unable to open the necessary socket for the promiscuous change operation. May be due to a shortage of file descriptors.

Unable to open socket for MTU determination
Returned by the facility for detailed interface statistics if the raw socket's opening sequence failed. The facility will abort.

Unable to open raw socket
IPTraf was unable to open the raw socket for packet capture. May be due to a shortage of file descriptors.

Unable to obtain interface MTU
The detailed statistics facility was unable to obtain the maximum transmission unit (MTU) for the selected interface. The facility will abort.

Specified interface not supported
The interface specified with the -i, -d, -s, -l or -z command-line parameters is not supported by IPTraf.

Specified interface not active
The interface specified with the -i, -d, -s, -l or -z command-line parameters is supported, but not currently activated.

Fatal: memory allocation error
May occur if you have too little memory to allocate for windows, the menu system, or dialog boxes. IPTraf tries to prevent further allocations if memory runs out during a monitor. However, this could also mean a bug if you're reasonably sure you're not out of memory. An instructional message on bug reporting follows this message.

This program can be run only by the system administrator
IPTraf normally does not allow anybody but uid 0 (root) to run it. This measure is included for safety reasons. See the section on recompiling the program below if you want to override this. This feature is built in, and not part of the configuration

Your TERM variable is not set
The TERM (terminal type) environment variable must be set to a valid terminal type so that the screen management routines can function properly. Set it to the appropriate terminal type. Linux consoles typically use a value called "linux".

Received TERM signal
Not related to the previous message. The TERM (terminate) signal is normally used to gracefully shut down a program. This message simply indicates that the TERM signal was caught and IPTraf is attempting to shut down as gracefully as possible.

Invalid option or missing parameter, use iptraf -h for help
The -i, -d, -s, -z or -l options were specified but no interface was specified on the command line. These parameters require a valid interface name (or all for -i or -l).

This message also appears if an unknown option is passed to the iptraf command.

Warning: unable to tag this process
IPTraf normally tags itself when it runs to prevent multiple instances of the statistical facilities from running. This message means the program was unable to create the necessary tag file. This may be due to a bad or improper installation. Try running the "make install" procedure.

Warning: unable to tag facility
IPTraf was unable to create the tag file for the facility you started. The facility will still run, but other instances of IPTraf that may be running simultaneously will allow the same facility to run. This may cause both instances of the facility to malfunction. This could be due to a bad disk or bad installation.

facility already active in another process
The facility you tried to start is currently running in another IPTraf process on the machine. This restriction is placed to prevent conflicts involving internal sockets or the log file.

Duplicate port/range entry
You entered a port number or range that was already added to the list of additional ports to be monitored by the TCP/UDP service monitor

No custom ports
There are no ports or port ranges earlier added. There's nothing to delete.

Can't start rvnamed; lookups will block
IPTraf cannot start the rvnamed daemon; probably due to a bad installation. IPTraf will fall back to blocking lookups.

Can't spawn new process; lookups will block
IPTraf cannot start a new process. This may be due to memory shortage. IPTraf will fall back to blocking lookups.

Fork error, IPTraf cannot run in background
IPTraf cannot start a new process, and can go into the background. This may be due to memory shortage. IPTraf aborts.

No memory for new filter entry
IPTraf was unable to allocate memory for a new filter entry. Most likely due to memory shortage.

Memory Low
This indicator appears if memory runs low due to a lot of entries in a facility. Should critical functions fail (window creation, internal allocation), the program could terminate with a segmentation violation.

IPC Error
This indicator appears if an error occurs receiving data from the rvnamed program (IPC stands for Interprocess Communication). This indication should not occur under normal circumstances. Report instances of this condition and the circumstances under which it happens. You may also include data from the rvnamed.log file.

Error opening terminal: terminal
The screen management routines cannot find the terminfo entry for your terminal. IPTraf expects the terminfo database located in /usr/share/terminfo. This error could occur when your terminfo database is located somewhere else.

See the section above on controlling the terminfo search path.

rvnamed Messages

Being a daemon, rvnamed does not send messages to the screen. It writes its messages to the file rvnamed.log in the IPTraf working directory.

Unable to open child communication socket
rvnamed was unable to open the communication endpoint for data reception from the children it creates. This is highly unusual, and should it occur, report the circumstances.

Unable to open client communication socket
rvnamed was unable to open the communication endpoint for data exchange with the IPTraf program. This is highly unusual, and should it occur, report the circumstances.

Error binding client communication socket
Error binding child communication socket
rvnamed was unable to assign a name to the indicated communication socket. This may be due to a bad, full, or corrupted filesystem.

Fatal error: no memory for descriptor monitoring
rvnamed ran out of memory. IPTraf will resort to blocking, and may freeze.

Error on fork, returning IP address
rvnamed had a problem spawning a copy of itself to resolve the IP address. rvnamed will simply return the IP address in its literal, dotted-decimal notation. IPTraf will still function normally. This may be due to lack of memory or a process limit hit.

Recompiling the Program

1. Change to the src directory and clear out the supplied binaries by entering
   make clean

2. Recompile by entering
   make

   at the prompt. You may want to recompile force the program to use your libraries and/or kernel sources, or to simply generate smaller executable files.

The distribution executable file is dynamically-linked ELF. It uses the shared C library, but the ncurses and panels libraries are linked in. With most systems, this program should work immediately after installation.

If you have the appropriate libraries and facilities, you can recompile the program to use the shared versions of the ncurses and panels libraries.

Recompiling requires:

• Linux 2.2.0 or later
• gcc-2.7.0 or later (2.7.2.3 or later for glibc2)
• ncurses-1.9.9e or later (earlier versions have problems with the Backspace key and updates of overlapping windows)
• GNU make

Makefile Options

The dirs.h header file also contains the default locations for the working directory and the names and locations of the configuration and log files. You do not need to change these, but you may do so if you'd rather place these files somewhere else.

Read the comments in the Makefile and dirs.h files for information on the various directives.

When compilation is complete, enter

make install

Kernel

The new kernel's raw packet capture facility has been extended since the last stable kernel release, and IPTraf now takes advantage of the new functionality, enabling it to count packets on a directional (incoming/outgoing) basis.

There is also a little concern regarding the Backspace key. Apparently the backspace key mapping (KEY_BACKSPACE) is considered unreliable, and is marked as such in ncurses versions as late as 1.9.9e, although tests on this version already worked. Tests for 1.9.4 failed; pressing the Backspace key yielded ^?. The Delete key works with no problem though. If you want the program to not recognize the Backspace key, you can enable the -DDISABLEBS directive in the Makefile.

With Ethernet and FDDI, IPTraf can receive packets in promiscuous mode (i.e. all packets on the LAN, regardless of their destination). Promiscuous mode is pointless on SLIP/PPP interfaces, since these things are point-to-point links.

IPTraf imposes no additional load on the network, except for DNS traffic if reverse name lookup is enabled. (Some setups use RPC calls to obtain service name information. This could also add UDP traffic to the network.)

License and Copyright for IPTraf

The software and accompanying documentation are distributed under the terms of the GNU General Public License, Version 2 or any later version, as published by the Free Software Foundation, Inc. Permission is granted to distribute and/or modify the software and the documentation under the terms of the license.

The software and accompanying documentation are distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR ANY PARTICULAR PURPOSE. For more details, see the GNU General Public License, in the COPYING file included in the distribution.

IPTraf uses header files that are part of the GNU C library and the Linux kernel distribution.

Additional structures were extracted from software copyrighted by the Regents of the University of California.

Linux is a registered trademark of Linus Torvalds

Pentium is a registered trademark of Intel Corporation.