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HSRP connectivity issues

Unanswered Question

HI,

We are facting loss of connectivity when HSRP enabled between the routers & linux server.


When HSRP is disabed the Linux box sends ARP requests and receives the corresponding ARP reply.

After sometime when HSRP is enabled,  the Linux box receives ARP requests from the STANDBY CISCO router.

This could be because the STANDBY router does not have the ARP cache entries for the Linux Box.

Can  you please let me know what is the expected behaviour and how the  ACTIVE and STANDBY routers are updating the ARP cache and Routing table .

Below are the some analysis (through wireshark) on each linux  interface. It seem that each interface is communicating with only one  particular IP address .


Before HSRP Disable:


eth2 (10.32.23.55)


10.32.23.55 ---- ARP request(unicast) ---->> 10.31.22.197 (Degault gateway)


10.32.23.55 <<---- ARP reply(unicast) ----   10.31.22.197 (Degault gateway)



eth3 (10.32.23.54)


10.32.23.54 ---- ARP request(unicast) ---->> 10.31.11.70 (router)


10.32.23.54 <<---- ARP reply(unicast) ----   10.31.11.70 (router)



eth4 (10.32.23.53)


10.32.23.53 ---- ARP request(unicast) ---->> 10.31.13.76 (router)


10.32.23.53 <<---- ARP reply(unicast) ----   10.31.13.76 (router)



eth5 (10.32.23.53)


10.32.23.52 ---- ARP request(unicast) ---->> 10.31.24.72 (router)


10.32.23.52 <<---- ARP reply(unicast) ----   10.31.24.72 (router)



After HSRP Enable:


eth2 (10.32.23.55)


10.32.23.55 ---- ARP request(unicast) ---->> 10.31.22.197 (Degault gateway)


10.32.23.55 <<---- ARP reply(unicast) ----   10.31.22.197 (Degault gateway)


  (ARP request sent by Standby router )


10.32.23.52 (eth5) <<---- ARP request(Broadcast) ----  10.32.23.50 (Standby router) virtual IP Address: 10.32.23.49


10.32.23.55 (eth2) <<---- ARP request(Broadcast) ----  10.32.23.50 (Standby router) virtual IP Address: 10.32.23.49


Can you please suggest something about above network behavior ?

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Sergey Fer Tue, 05/22/2012 - 04:49
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Why not? Every host has a right to send ARP request. May be your Linux server is configured with some sort of dynamic routing? It wil be good to see your server's IP settings.

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