Forum Discussion
Paul_108843
Nimbostratus
NimbostratusLTM Log Files
I need to be able to see tcp traffic between client and F5 and between F5 and pool memebers. Anybody knows how I can setup and view that? Thanks
- JRahm
Admin
if you have cli access, you can use tcpdump. You can specify a file for clientside/serverside separately or you can use the special interface 0.0 to capture from all links. 
nitassEmployee
by default, system log (e.g. /var/log/ltm) does not include application traffic. if you want to log application traffic, you can use irule.
e.g.
Log Http Tcp Udp To Syslogng
https://devcentral.f5.com/wiki/iRules.LogHttpTcpUdpToSyslogng.ashx
MOHIT_125417Altostratus
Hi Nitaas, Can't i see tcp traffic between client and F5 and between F5 and pool memebers from F5 LTM cli??? If yes can you please shrae the commands to check it.- nitassdo yo mean packet? if yes, you can run tcpdump. tcpdump -nni 0.0 -s0 host x.x.x.x or host y.y.y.y x.x.x.x is client ip y.y.y.y is pool member ip
shaggy(more tcpdump info) - https://support.f5.com/kb/en-us/solutions/public/0000/400/sol411.html There is also the command "tmsh show sys connection" which will show you current connection details
nitass_89166Noctilucent
by default, system log (e.g. /var/log/ltm) does not include application traffic. if you want to log application traffic, you can use irule.
e.g.
Log Http Tcp Udp To Syslogng
https://devcentral.f5.com/wiki/iRules.LogHttpTcpUdpToSyslogng.ashx- MOHIT_125417Hi Nitaas, Can't i see tcp traffic between client and F5 and between F5 and pool memebers from F5 LTM cli??? If yes can you please shrae the commands to check it.
- nitass_89166do yo mean packet? if yes, you can run tcpdump. tcpdump -nni 0.0 -s0 host x.x.x.x or host y.y.y.y x.x.x.x is client ip y.y.y.y is pool member ip
- shaggy(more tcpdump info) - https://support.f5.com/kb/en-us/solutions/public/0000/400/sol411.html There is also the command "tmsh show sys connection" which will show you current connection details
You can capture client side traffic and responding server side traffic using below command::
tcpdump -vvnni 0.0:nnnp -s0 host x.x.x.x and port yy- where x.x.x.x is Virtual IP and yy is virtual server port number
If you want to traffic for a specific client then::
tcpdump -vvnni 0.0:nnnp -s0 host x.x.x.x- where x.x.x.x is client IP
If you want write captured traffic to a file to review later in wire shark or some other tool use 'w' option and provide path to the file
tcpdump -vvnni 0.0:nnnp -s0 -w /var/tmp/capture.pcap host x.x.x.x
