Not freeing up tcp port fast enough?

Hello,

I'm implementing a tcp server and an associated client. One feature about 
this server is that the client can invoke a remote restart command which 
causes the server to restart itself. This means that it will stop what it's 
doing, remove all clients, close all sockets and then restart from main() 
again.

Now I've been trying this out but in some rare cases I'm getting problems 
where the restart fails. The reason is that Solaris doesn't free up the port 
fast enough and thus the server will say that another application is using 
the same port when calling bind().

Whats the common way to handle this? I have not seen it on any other unix 
systems so far.

Thanks.

-- Henrik 

You've probably already thought of this, but are you using SO_REUSEADDR
with setsockopt()?

-- 
Brandon Hume    - hume -> BOFH.Ca,  http://www.**--****.com/ 

Thanks for the suggestion. I did not even know it existed. However couldn't 
this affect that data mistakenly will be sent to the wrong socket (which is 
about to expire by the OS) in the process of switching?
Even if it happens I assume it will lead to an error on the client side.

-- Henrik 

TIME_WAIT is there for a reason.  So, yes, you lose something by reusing
the socket early.  Your choice is to reuse it early or not.  There isn't
much else you can do.


There are a variety of (hopefully very obscure) things that can happen.

 http://www.**--****.com/ 

-- 
Darren Dunham                                            XXXX@XXXXX.COM 
Senior Technical Consultant         TAOS             http://www.**--****.com/ 
Got some Dr Pepper?                           San Francisco, CA bay area
         < This line left intentionally blank to confuse you. >

Indeed, TIME_WAIT is there for a reason, but SO_REUSEADDR does not (or
at least should not) short-circuit TIME_WAIT or any other state.  What
it does is allow an application to have a new instance of its LISTEN
endpoint while there are still previous connections in states "beyond"
the LISTEN state.

rick jones
-- 
Wisdom Teeth are impacted, people are affected by the effects of events.
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

*blink*

I didn't get exactly what you meant at first because I was confusing the
binding and the lack of connection states on the port.  I see I had
managed to misunderstand the details about REUSEADDR.   

-- 
Darren Dunham                                            XXXX@XXXXX.COM 
Senior Technical Consultant         TAOS             http://www.**--****.com/ 
Got some Dr Pepper?                           San Francisco, CA bay area
         < This line left intentionally blank to confuse you. >