Maintained by: NLnet Labs

[Unbound-users] Release of unbound 1.1.0

Aaron Hopkins
Thu Nov 20 20:23:04 CET 2008


On Thu, 20 Nov 2008, Wouter Wijngaards wrote:
> I am curious why you are getting the accept failure. What resource is
> temporarily unavailable?  Is the kernel running out of TCP buffers? Is
> there a problem with ulimit(number of files) ?

"Resource temporarily unavailable" is EAGAIN, I think.  Which is documented
in Linux's man accept(2) as:

   EAGAIN or EWOULDBLOCK
       The socket is marked non-blocking and no connections are present to be
       accepted.

There is no guarantee that select() returning activity on a listen()ing
socket will result in a successful accept().  I'm guessing something is
making a TCP connection to this port, causing select() and friends to return
that there's work to be done, but closing the connection before unbound
accept()s.

> The above fix is in svn trunk for 1.1.1 release.

Thanks for the fast turnaround.  I'll try it out today.

                                     -- Aaron