I've never dealt with the JavaMail API so I can't really give you any
details. I'm sure there are more appropriate forums for discussing those
issues.
The sockets are going away when you stop Tomcat for one of two reasons.
First, there's code in your servlets' destroy() method that is actively
closing the connections or the VM is forcefully closing them as it shuts
down.
I would guess (and this really is a guess because I've never used JavaMail
or IMAP) that the IMAP server is shutting down the connection from its side,
say for inactivity, and you're still holding on to a reference to some
object on your side that's holding open the client half of the socket. At
any rate, this isn't a topic that's relevant to tomcat-dev.
Marc Saegesser
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, August 21, 2001 1:52 PM
> To: [EMAIL PROTECTED]
> Subject: RE: imap close_wait with Tomcat 3.2.1
>
>
> Hi,
> Thank you Marc for your reply.
>
> As a matter of fact I am using JavaMail API to handle
> my communication to the IMAP server. So all the lower
> level sockets, etc., are transparent to me.
>
> Is there a way I can look at this? And why do I see
> the sockets being released once I shutdonw Tomcat?
>
> Thanks.
> Lumi.
>
> --- Marc Saegesser <[EMAIL PROTECTED]> wrote:
> > A socket enters the CLOSE_WAIT state when it
> > receives a FIN packet from the
> > other side. It remains in this state until the
> > application issues a close()
> > on the socket. At that point a FIN packet is sent
> > and the socket enters the
> > LAST_ACK state until the associated ACK packet is
> > received. The Stevens
> > _TCP/IP Illustrated, Volume 1_ book is almost
> > required reading for anyone
> > doing TCP/IP programming.
> >
> > I don't think this is a Tomcat problem, but most
> > likely something in your
> > servlet code that isn't properly closing down the
> > connections to the IMAP
> > server (or more probably, not handling the situation
> > where the IMAP server
> > closes its end of the connection).
> >
> >
> > Marc Saegesser
> >
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED]]
> > > Sent: Tuesday, August 21, 2001 1:05 PM
> > > To: [EMAIL PROTECTED]
> > > Subject: imap close_wait with Tomcat 3.2.1
> > >
> > >
> > > I am running a production server with Apache
> > 1.3.14
> > > and Tomcat 3.2.1. I have developed a
> > > JSP-JavaBeans-Based WebMail that runs on this RH
> > Linux
> > > 7.1 server.
> > >
> > > While debuging I noticed that if I logout of the
> > > webmail (click logout) I see the connection to the
> > > imap server being closed. But somehow, after
> > several
> > > users accessing the site, I notice, using netstat
> > -a
> > > imap, there is a growning number of close_wait
> > > sockets. Eventually I get a connection failure
> > > exception if I try to login. That is because there
> > are
> > > no more sockets available to the server.
> > >
> > > I read here and there that for some reason Tomcat
> > is
> > > not releasing those sockets. Does it have to do
> > with
> > > the possibility that some users just close the
> > browser
> > > instead of pressing logout?
> > >
> > > When I stop and start Tomcat I notice that all the
> > > close_wait sockets are released. Which makes me
> > feel
> > > it is a problem with my code/Tomcat's.
> > >
> > > By any means how can I fix this problem. It is
> > getting
> > > irritating to repeatedly stop and start tomcat
> > > whenever I get that exception.
> > >
> > > With the site load growing I am affraid that the
> > > server will crash every 5 minutes. Now I have to
> > > restart every other day.
> > >
> > > Thanks in advance.
> > >
> > > Lumi
> > >
> > > __________________________________________________
> > > Do You Yahoo!?
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> >
>
>
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