Re: Configure server firewall request/response

Martin Gainty <mgainty@xxxxxxxxxxx> · Fri, 29 May 2009 09:52:15 -0400

Here are 3 $POSGRES_HOME/data/postgresql.conf parameters which may help 

tcp_keepalives_idle (integer)
        On systems that support the TCP_KEEPIDLE socket option, specifies the
        number of seconds between sending keepalives on an otherwise idle
        connection. A value of 0 uses the system default. If TCP_KEEPIDLE is
        not supported, this parameter must be 0. This option is ignored for
        connections made via a Unix-domain socket.

tcp_keepalives_interval (integer)
        On systems that support the TCP_KEEPINTVL socket option, specifies how
        long, in seconds, to wait for a response to a keepalive before
        retransmitting. A value of 0 uses the system default. If TCP_KEEPINTVL
        is not supported, this parameter must be 0. This option is ignored
        for connections made via a Unix-domain socket.

tcp_keepalives_count (integer)
        On systems that support the TCP_KEEPCNT socket option, specifies how
        many keepalives may be lost before the connection is considered dead. 
        A value of 0 uses the system default. If TCP_KEEPCNT is not
        supported, this parameter must be 0. This option is ignored
        for connections made via a Unix-domain socket.

if all 3 parameters are left at 0 then the OS is supplying the keepalive parameters
here are my keepalive parameters from $POSTGRES_HOME/data/postgresql.conf
# - TCP Keepalives -
# see 'man 7 tcp' for details

#tcp_keepalives_idle = 0        # TCP_KEEPIDLE, in seconds;
                    # 0 selects the system default
#tcp_keepalives_interval = 0        # TCP_KEEPINTVL, in seconds;
                    # 0 selects the system default
#tcp_keepalives_count = 0        # TCP_KEEPCNT;
                    # 0 selects the system default

does this help?
Martin Gainty 
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> Subject: [GENERAL] Configure server firewall request/response
> Date: Fri, 29 May 2009 15:22:16 +0200
> From: Lars.Carlsson@xxxxxxxxxx
> To: pgsql-general@xxxxxxxxxxxxxx
> 
> 
> Hi
> I use a .net ODBC connection and the connection to Pgsql db is though a firewall that only allow request and a answer to the response.
> 
> I some times get Error from the client
> 
> "The connection has been disabled. ---> System.Data.Odbc.OdbcException: ERROR [08S01] No response from the backend;"
> 
> I check the firewall logs and it seems like some responses get blocked in the firewall could this be slow response or some kind of keep alive response.
> Are there some settings to make the Pgsql db server to work better with a firewall request/response the KeepAlive is turned off.
> 
> regards
> Lars 
> 
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