is it possible to synchronize the states of TCP proxies in real time (for real-high-availability of SLB)?

Posted by Song on Server Fault See other posts from Server Fault or by Song
Published on 2011-11-08T18:24:33Z Indexed on 2012/10/28 17:03 UTC
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load-balancing

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tcp

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high-availability

Consider that there are two server load balancers working in the tcp proxy mode (e.g., for L7 load balancing). Is it possible to synchronize their states in real time so that they can be a backup for each other? in case that one is down, the other still has all necessary states to uninterruptedly support all existing TCP connections.

I understand that this is hard, but I am wondering whether any free/commercial LB already supports this feature.

Thank you!

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