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This command invokes the packet capture ability of the Lantronix Local Manager. The secondary Ethernet port can be configured to monitor a SPAN port of a switch and capture packets matching a variety of conditional statements. Only the packets destined for the secondary Ethernet port meeting the regular expressions defined in the conditional statements are captured.

A single capture is available to view in text mode or it can be transferred to another system in text or pcap form.

The capture will spool up to 5 MB of capture detail.


  • The Local Manager's Secondary Ethernet port must be in capture mode.

Enable Capture Mode

Use the config system secondary command to enable capture mode. If capture mode is not enabled, an error message will be displayed when trying to use the capture command.

[admin@LantronixLM]# capture
Capture is not currently enabled. To enable use 'config system secondary'.

[admin@LantronixLM]# config system secondary
--- Existing  Values ---
Type: bonded
Bonding Link: yes
[E1] Primary Ethernet Link: yes (bonded active)
[E2] Auxiliary Ethernet Link: no (bonded)
[E3] Internal SFP Ethernet Link: no (bonded)
Change these? (y/n) [n]: y
--- Enter New Values ---
Type [bonded]: capture
speed/duplex [auto]: 
Warning: Remote connections may be lost if you commit changes.
Do you want to commit these changes? (y/n): y


usage: capture [options]

--- options ---

  -size <arg>   [integer]

    capture -size 1514

      host | net | port 80

      capture host and port 80 or 443

  Direction source or destination
      src or dst | src | dst | src and dst

      capture src and dst port 80 and 443 or 8443

      ip | Ip6 | icmp | arp | udp | tcp [portrange] | vlan

      capture ip6 -size 1514 src 2001:470:b851:10:0:0:0:19 and dst port 80
      capture tcp dst portrange 20-21

  Packet size:
      greater | less

      capture greater 1024
      capture less 68


[admin@LantronixLM]#capture ip6 -size 1514 src 2001:470:b851:10:0:0:0:19 and dst port 80
Press 'x' or Ctrl+C to stop capturing packets.
64 bytes
Capture stopped.


4.4 - This command was introduced

Related commands

  • show capture