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hightower_m's avatar
hightower_m
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Apr 21, 2014

MS IIS to SQL Server through F5 forwarding server and tcp resets

So I have a 11.2.1 LTM setup that has two IIS servers behind it. They use the F5 as default gateway and communicate out via the forwarding virtual server - most specifically to our SQL servers. I'm seeing some odd issues in our application where the IIS servers are closing the connections to the SQL servers. Seems like TCP resets. It appears to be random at this point. Since the connection essentially times-out as far as SQL is concerned the next connection to SQL actually tries to hit the SQL mirror server. This doesn't work because SQL has really failed over.

 

I have some tcp dumps to look through more but has anyone seen anything peculiar in regards to SQL connections through the F5 virtual forwarding server? Maybe some settings to tweak.

 

thanks

 

application delivery
availability
LTM
management

2 Replies

  • hightower_m's avatar
    hightower_m
    Icon for Nimbostratus rankNimbostratus
    Apr 22, 2014

    I haven't been able to say that accurately at this time. I did see that article and set up that logging. I didn't get a chance to watch the counters long but there were some 3WHS logged and I think some bad checksum. I'll have to check more tomorrow. It's a very intermittent problem and could be a totally different thing. All that has been verified is that the IIS server side is closing the connection before it should.

     

    thxs