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itxali_313821's avatar
itxali_313821
Icon for Altocumulus rankAltocumulus
Apr 24, 2017
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Server port not accessible from F5

Hi Gurus,   We have specific service running on server with port 3010 I can able to ping that server from F5 CLI, Telnet that server on port 22, 80 to check these service port accessible. After ve...
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  • itxali_313821's avatar
    itxali_313821
    Apr 27, 2017

    Thanks all for your help, actually issue was on Firewall there was policy which allows only ping, http & ssh traffic.

     

    My F5 management IP was 10.11.5.x/24 network, server was in 10.11.1.x/24 network so I was tracing on firewall using source IP F5 (10.11.5.x) destination server IP (10.11.1.x) I was getting no trace logs so I thought traffic was not blocked by firewall.

     

    After more troubleshooting, I enabled tcpdump on server in (10.11.1.x) network, so I came to know F5 was doing NAT when forwarding its traffic. Like 10.11.5.x network was NATTed to 10.11.3.x network, this was not allowed on firewall. After enabling this network for 3010 port on firewall it worked.

     

    Thanks all my concept was source and destination IP's never change util unless it is NATTED, still looking how F5 is NATTING its management IP from 10.11.5 to 10.11.3.

     

    Thanks.

     

Snl's avatar
Snl
Icon for Cirrostratus rankCirrostratus
Apr 24, 2017

do u have routedomain configured or try telnet to the vip and ensure under same vip pool u allow the node with correct port also you can do tcpdump and see whether you are getting the response from server or not , there are few scenario were you might have firewall in between F5 and server then you need to ensure you have allowed the self ip's over firewall for communication towards server.

 

use below tcp dump - x.x.x.x is server ip

 

tcpdump -ni 0.0:nnnp host x.x.x.x -s0 -w /var/tmp/traffic.pcap -vvv