general/7603: Server hanging when faced with network bottlenecks

[Usman Wahid <ms...@yahoo.com>]

>Number:         7603
>Category:       general
>Synopsis:       Server hanging when faced with network bottlenecks
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sun Apr 22 00:50:00 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     mswahid@yahoo.com
>Release:        1.3.12
>Organization:
apache
>Environment:
Linux 2.2.12-20smp #1 SMP i686 (RedHat Linux 6.1)
>Description:
we have a redhat linux 6.1 server running Apache 1.3.12 using mod_perl. the site is very busy but works normal when it is accessible from external network. the problem is when a major part of internet can't connect to the server properly (at normal speed) the apache seems to hang and doesn't respond. the surprising thing is that at that time apache doesn't respond even if we connect from local host. if we try to restart apache or the server it remains okay for a few seconds but then again it seems to hang from local host. probably it is due to the fact that immediately after restarting there are many requests for apache. we are also using nmap to scan local ports and at the time of hanging of apache, port 80 is shown as filtered. there are no errors in server logs. the settings are: MinSpareServers 20, MaxSpareServers 40, StartServers 30, Maxclients 300 and MaxRequestsPerchild 0. the question is why we can't connect from the localhost when httpd restarts okay without any errors and there is no change in the configuration. the most surprising thing is that things are back to normal when there is no network problem.
>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
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