TCP Dump
This is a tool to sniff the packet, when you want to examine that the expected packet really reached a node. You can run the tcpdump utility to sniff the packet headers on the network and save them on a dump file.
To use tcpdump:
- Select Maintenance > Troubleshooting > TCP Dump to display the configuration page.
- Complete the configuration as described below.
- Click Start Sniffing to start the tcpdump process.
- Initiate the action you want to debug, such as a user sign in.
- Click Stop Sniffing to write the tcpdump output to the screen.
- Click Get to save the output to a file, or click Delete to clear the output.
Settings |
Guidelines |
|
---|---|---|
TCP Dump Status |
Displays whether the utility is stopped or running. |
|
Interface |
Select the ports on which to sniff. |
|
VLAN Port |
Select the VLAN port. |
|
Promiscuous mode |
Select a promiscuous mode option. |
|
Filter |
Specify a filter expression. For information about TCP dump filter expressions, see the UNIX man page. |
|
|
Example |
Result |
tcp port 80 |
Sniffs packets on TCP port 80. |
|
port 80 |
Sniffs packets on TCP or UDP port 80. |
|
ip |
Sniffs the IP protocol. |
|
tcp |
Sniffs the TCP protocol. |
|
dst #.#.#.# |
Sniffs the destination IP address specified, where #.#.#.# is a valid IP address. |
|
src #.#.#.# |
Sniffs the source IP address specified, where #.#.#.# is a valid IP address. |
|
port 80 or port 443 |
Sniffs on port 80 or port 443. |
|
src #.#.#.# and dst #.#.#.# |
Sniffs the source and destination IP addresses or hosts specified, where each #.#.#.# represents a valid IP address. |
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tcp port 80 or port 443 and dst #.#.#.# and src #.#.#.# |
This example shows how to specify multiple parameters to create a filter that sniffs on TCP port 80, or on TCP or UDP port 443, and on the destination and source ports, where each #.#.#.# represents a valid IP address. |