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Yehey_100134
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Feb 01, 2011

Unable to ping Virtual server

Hi All,

 

 

I'm unable to ping our virtual server (192.168.100.5) from our monitoring system. When i performed a tcpdump all i can see is icmp request but no replies from the LB.

 

 

 

I compared the configs on other virtual servers and all i can see is that arp is not enabled on 192.168.100.5. Might this be causing the issue?

 

 

 

Regards,

 

 

 

Yehey

 

5 Replies

  • Hi Yehey,

     

     

    You'll definitely want ARP enabled on the virtual address:

     

     

    b virtual address 10.1.0.15 list

     

    virtual address 10.1.0.15 {}

     

    [root@ve1:Active] config ping 10.1.0.15

     

    PING 10.1.0.15 (10.1.0.15) 56(84) bytes of data.

     

    64 bytes from 10.1.0.15: icmp_seq=1 ttl=255 time=4.09 ms

     

    64 bytes from 10.1.0.15: icmp_seq=2 ttl=255 time=1.13 ms

     

     

    --- 10.1.0.15 ping statistics ---

     

    2 packets transmitted, 2 received, 0% packet loss, time 1026ms

     

    rtt min/avg/max/mdev = 1.131/2.612/4.094/1.482 ms

     

     

    [root@ve1:Active] config b virtual address 10.1.0.15 arp disable

     

     

    [root@ve1:Active] config ping 10.1.0.15

     

    PING 10.1.0.15 (10.1.0.15) 56(84) bytes of data.

     

     

    --- 10.1.0.15 ping statistics ---

     

    3 packets transmitted, 0 received, 100% packet loss, time 2082ms

     

     

    Aaron
  • HI Aaron,

     

     

    I enabled ARP on that VIP but im still not able to ping it from a local server.

     

     

     

    [root@lb1:Active] config tcpdump -i vlan1 host 192.168.100.5

     

    tcpdump: listening on vlan1

     

    04:45:14.277739 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:15.277727 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:16.277306 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:17.277723 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:18.277376 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:19.276774 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:20.276336 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:21.276775 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

    04:45:22.276277 192.168.100.1 > 192.168.100.5: icmp: echo request (DF)

     

     

     

     

    [root@lb1:Active] config b virtual address 192.168.100.5 list

     

    virtual address 192.168.100.5 {

     

    route advertisement enable

     

    mask 255.255.255.252

     

    arp enable

     

     

     

     

     

     

    Any ideas on what might be hindering the icmp requests?

     

     

     

     

     

    Thanks,

     

     

     

    Yehey

     

  • Do you have 192.168.100.5 defined as a standard virtual server as well? If so, can you make sure it's set up as a host as opposed to a network virtual server?

     

     

    Aaron
  • We utilize two LB's for failover in case the primary goes down. 192.168.100.6 is the primary and configured as a host while 192.168.100.5 is the secondary and is configured as a network. We have a couple of vip configured with this setup and this is the only one i can't ping.

     

     

    I'm able to telnet to the vip and it forwards me to the primary node on the pool. Basically, the LB is working as designed, but im curious why it does not respond to pings. I checked the vlan configs on our router and all is good. We're running on Version: 9.4.1.

     

     

     

    Yehey

     

  • It could be because of this: https://support.f5.com/kb/en-us/solutions/public/16000/200/sol16284.html