---
name: "axlisten"
section: "1"
platform: "linux"
package: "ax25-apps"
version: "0.0.8-rc5+git20230513+afc4a5f-3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/axlisten"
---

# axlisten(1)

monitor AX.25 traffic

## NAME

axlisten - monitor AX.25 traffic

## SYNOPSIS

**axlisten \[-8\] \[-a\] \[-c\] \[-h\] \[-i\] \[-p port\] \[-r\] \[-t..\] \[-v\]**

## DESCRIPTION

**Axlisten** uses SOCK\_PACKET facilities to provide a network monitor of all AX.25 traffic heard by the system. Since KISS is implicitly promiscuous no special driver configurations are needed.

This version displays standard AX.25, PE1CHL extended AX.25, NET/ROM, Rose, ARP, IP, ICMP, TCP and UDP. It also displays IP, TCP, ICMP, TCP and UDP encapsulated within NET/ROM frames. The program also displays AX.25 and IP encapsulated within an IP frame, but see RFC1326 for reasons not to do so.

**Axlisten** makes an attempt at decoding some of the more common routing protocols. RSPF and RIP (both “normal” and G8BPQs RIP98) are traced. JNOS style NET/ROM node polls are also displayed.

**Axlisten** can use colors to make the output more readable. The ncurses library is used to accomplish this. **Color support defaults to being disabled,** and the **-c** parameter is used to enable it.

## OPTIONS

- **-8**

  Indicates that the terminal is capable of printing 8-bit characters. This parameter is required for the -i parameter to work.

- **-a**

  Allow for the monitoring of outgoing frames as well as incoming ones.

- **-c**

  Enable color support.

- **-h**

  Dump the data portion of the packet in both hexadecimal and ASCII. The default is to display data as ASCII only.

- **-i**

  Map IBM codepage 437 characters 128-158 to their ISO-Latin-1 equivalents. This is a hack for scandinavian users. This parameter is only valid when used with the -8 and -c parameters.

- **-p port**

  Monitor only those frames received on a particular port, by default all AX.25 devices are monitored.

- **-r**

  Dump the data portion in a "readable" fashion, which is more suitable for tracing plaintext AX.25 traffic. CR-LF conversion is done.

- **-t**

  Don't print a timestamp on each dump line.

- **-tt**

  Print an unformatted timestamp on each dump line.

- **-ttt**

  Print a delta (micro-second resolution) between current and previous line on each dump line.

- **-tttt**

  Print a timestamp in default format proceeded by  date  on  each dump line.

- **-ttttt**

  Print a delta  (micro-second  resolution)  between current and first line on each dump line.

- **-v**

  Display the version.

## FILES

/etc/ax25/axports

## SEE ALSO

[**axcall**(1)](/axcall/1.md), [**mheard**(1)](/mheard/1.md), **beacon**(1), [**ax25**(4)](/ax25/4.md), [**netrom**(4)](/netrom/4.md), [**rose**(4)](/rose/4.md), [**kissattach**(8)](/kissattach/8.md).

## BUGS

**Axlisten** does not validate the checksums of frames that support them (ie IP), therefore corrupt frames will be displayed with bogus values. The MSS of a TCP frame that contains that option is not displayed.

## AUTHORS

```
Alan Cox GW4PTS <alan@cymru.net>
Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>
Phil Karn KA9Q <karn@qualcomm.com>
Heikki Hannikainen OH7LZB <oh7lzb@sral.fi>
Scott Miller N1VG <scott@opentrac.org>
```