Re: Question

WF Software wrote: > <snip> > > It's normal for connections to end up in FIN_WAIT_2 when the server > is killed. (A good server catches termination signals and cleans up > its connections, and a good sysadmin doesn't kill such a server with > SIGKILL, so this problem shouldn't exist. But we can't count on such > being the case.) > > According to the TCP/IP spec (ie. the dazzling panoply of RFCs, a > connection in FIN_WAIT_2 that was owned by an application that's > gone away will never transition to another state. However, many > implementations terminate FIN_WAIT_2 connections that were fully > closed locally after 10 minutes and 75 seconds, which is what you're > seeing. > > A sockets-based TCP server should *always* set SO_REUSEADDR on the > master socket before calling bind, so that it can bind again if > there are residual connections in FIN_WAIT_2 or CLOSE_WAIT or > whatever. > > This is probably one of two the most common TCP sockets programming > errors. The other is setting SO_LINGER off, which you should never > do. (If you know enough about what SO_LINGER does to contradict > that statement, then you know about the extremely unusual architectures > where disabling it makes sense.) > > Paul Watson # I don't suffer from > WF Software Ltd. # stress, I'm just > Tel. (+44) 1436 674729 # a carrier > Fax. (+44) 1436 678693 # > www.wfsoftware.co.uk Hey, thanks, Paul. That diagnoses an intermittent problem I get with Lotus Notes connections. Must be the server (it's on NT, of course...). It's not my responsibility, fortunately, but it had our network folk baffled. -- Peter Lancashire Information Systems Specialist, Bayer plc Eastern Way, Bury St Edmunds, Suffolk, IP32 7AH, UK Tel: +44-1635-562258, Fax: +44-1635-562281 --- If all else fails, read the instructions AND the release notes. All opinions are my own and not those of Bayer plc. My Internet plumbing does not allow me to mail and post news together. Sorry. --- Join Infuse, the UK Informix User Group at http://www.infuse.org.uk/