Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

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Sumanta_88744's avatar
Sumanta_88744
Icon for Cirrus rankCirrus
Sep 07, 2014

Creating an active-active DSC configuration with OSPF routing on 11.x

Hi Experts   I have to do a deployment of active/active VIPRION 2400 chassis, running 2250 blades. As per below link, we need to create two traffic groups for each VLAN. How will the default routi...
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Kevin_Davies_40's avatar
Kevin_Davies_40
Icon for Nacreous rankNacreous
Sep 10, 2014

Sumanta,

 

You should not have to advertise any routes for virtual servers. The router attached to that VLAN where the virtual's are listening should automatically advertise the attached network if its participating in OSPF. When the traffic arrives at the router then it will forward the incoming traffic to the virtual server. Which F5 it goes to will depend entirely on which BIGIP is currently hosting that virtual servers address. This is determined by which BIGIP is active for the traffic group. This will automatically change when a failover occurs.

 

Again on the server side of the BIGIP the the adjacent router will advertise the attached network through OSPF. Traffic leaving the BIGIP towards the server will use SNAT to change the source address to the floating IP address of the traffic group (assumes SNAT automap). Again this address is currently hosted by whichever BIGIP is currently hosting the that floating IP address. This is determined by which BIGIP is active for the traffic group. This will automatically change when a failover occurs.

 

There is no need to advertise specific routes for BIGIP traffic. The adjacent routers should look after all of that for you. The BIGIP's will respond based on which traffic group's they are currently hosting. This is all done at the MAC level in the attached VLANS.

 

Kevin_Davies_40's avatar
Kevin_Davies_40
Icon for Nacreous rankNacreous
Sep 11, 2014
Yes, auto last hop should always be enabled. It means you do not have to provide routes back to the client. I am surprised you have any routes at all if the servers are in the same VLAN. You only need routes if your servers are in a network elsewhere. If servers are talking to a VIP they will go to that VIP's address. If there is return traffic from a server it will go to the SNAT address. If however, your are doing forwarding virtual servers then you need to tell us as they have special requirements.