Re: Bogus bind() warnings

Tom Lane wrote:

>Peter Eisentraut <peter_e@gmx.net> writes:
>  
>
>>When I start up with -i, I get the following log:
>>LOG:  could not bind IPv4 socket: Address already in use
>>    
>>
>
>  
>
>>There is no other postmaster running anywhere.  I suspect that this has to
>>do with IPv6.  This is a SuSE 8.something machine that is relatively fully
>>IPv6 enabled.
>>    
>>
>
>Is it possible that that kernel considers binding to an IPv6 port to
>conflict with binding to the "same" port number as an IPv4 port?
>
>IIRC that was the behavior we once expected would happen, but later
>found out that most kernels don't (yet?) act that way.  The present
>design of trying to bind to both IPv6 and IPv4 sockets would be
>unnecessary if the kernels acted more rationally.
>
>  
>

I have seen this before, and reported it, but can't find the thread 
right now.

On Linux with IP6 enabled, IP4 is tunnelled over IP6 - they *are* the 
same sockets, AFAIK.

Didn't we put in a patch after lengthy discussion that fixes things from 
a pg_hba.conf POV exactly to handle this (i.e. to match an IP4 address 
in the file with the corresponding IP6 address: n.n.n.n/x -> 
::ffff:n.n.n.n/96+x )?

I also recall someone saying this would change in later versions of Linux.

cheers

andrew