Find the answer to your Linux question:
Results 1 to 3 of 3
Hello, I have a problem with tcp keep alive between a M$ SQL Server 2008 and a SUSE Linux Enterprise Server 11 SP1 and sql queries that take a longer ...
Enjoy an ad free experience by logging in. Not a member yet? Register.
  1. #1
    Just Joined!
    Join Date
    May 2011
    Location
    Germany
    Posts
    2

    unanswered tcp keepalive packets


    Hello,

    I have a problem with tcp keep alive between a M$ SQL Server 2008 and a SUSE Linux Enterprise Server 11 SP1 and sql queries that take a longer time. With a standalone M$ SQL Server 2008 everything works fine. But with a clustered M$ SQL Server 2008 the network connection will be closed after 30s.

    With a tcpdump i could see:
    The linux server opens a database connection to the M$ SQL server and put the query. After 30s the SQL server sends a tcp keep alive package.
    The package from the standalone M$ SQL server will be answered correct and the connection stays alive. The package from the clustered SQL server will not be answered by the linux server.

    Kernel version of the SUSE Linux system: 2.6.32.29-0.3-default #1 SMP 2011-02-25 13:36:59 +0100 x86_64 x86_64 x86_64 GNU/Linux
    I have attached a tcpdump with the working connection and a tcpdump with the dropped keepalive packets.

    I'm deeply greatful, if somebody could help me.

    Ulrich
    Attached Files Attached Files

  2. #2
    Just Joined!
    Join Date
    Jun 2011
    Location
    Vancouver, BC
    Posts
    1
    We are having exactly the same problem. Our environment is SQL Server 2008 R2 with Redhat Linux and JBoss app server.

    There's no problem with a standalone DB, but the connection drops when the DB is clustered. It looks like the keepalive packets are not recognized by Linux for some reason.

    Did you find any solution?

  3. #3
    Just Joined!
    Join Date
    May 2011
    Location
    Germany
    Posts
    2
    Hi,
    we did some more investigations. On the SUSE system is kernel 1.6.32.29. I have installed the original kernel 1.6.32.41 from kernel.org and the problem disappears. But we can't use this kernel, because we use a storage connected to the server. This storage provides a driver which only support SUSE or RedHat kernels.
    An other thing I tried, was to change the keepalive parameters this way, that the linux server first sends the keepalive packages, which will be answerd by the M$ SQL server. It's a workaround, but it works!

    Ulrich

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •