Bug 1807664

Summary: Apache stops processing requests approximately once per week
Product: Red Hat Enterprise Linux 8 Reporter: Suzanne <olsonsuzanne88>
Component: httpdAssignee: Luboš Uhliarik <luhliari>
Status: CLOSED WONTFIX QA Contact: rhel-cs-infra-services-qe <rhel-cs-infra-services-qe>
Severity: high Docs Contact:
Priority: unspecified    
Version: 8.1CC: jorton, luhliari, pasik
Target Milestone: rc   
Target Release: 8.0   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
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Clone Of: Environment:
Last Closed: 2021-08-26 07:27:10 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
netstat and strace outputs
none
Logs from another stuck instance none

Description Suzanne 2020-02-26 21:10:46 UTC
Created attachment 1666085 [details]
netstat and strace outputs

Description of problem:
Apache server stops processing requests approximately once per week.

There are 12 virtual hosts configured on the server. Some are running PHP (WordPress) sites, and some mod-mono apps.

The problem usually starts manifesting itself on one random virtual host first, but then spreads to the rest of them within the next few minutes.

Connections to Apache get stuck in the CLOSE_WAIT state and a restart of the httpd service is required.

I am attaching netstat and strace outputs in the log.txt file. Output of the 'top' is normal (CPU load is normal, there is sufficient free memory, ...) and 'lsof | wc -l' also returns a normal value (last time it was 137063, which does not seem to be any different than when everything is working fine).

There are no errors logged in the Apache's error_log file or RHEL's /var/log/messages file while the requests are not being processed.

I have increased the following system parameters, but that did not solve the problem:
net.ipv4.tcp_max_syn_backlog=8192
net.core.somaxconn=4096

What could be the cause?

Version-Release number of selected component (if applicable):
httpd 2.4.37-16

How reproducible:
It happens approximately once per week.

Steps to Reproduce:
Steps to reproduce are unknown.

Comment 1 Suzanne 2020-03-06 11:06:58 UTC
Do you need any additional information in regards to this bug report?

Please let me know.

Comment 2 Suzanne 2020-03-20 19:50:57 UTC
Created attachment 1672029 [details]
Logs from another stuck instance

I am attaching log file (output of lsof and strace) of another stuck instance of Apache.

Comment 4 Joe Orton 2021-04-22 14:37:07 UTC
Thank you for taking the time to report this issue to us. We appreciate the feedback and use reports such as this one to guide our efforts at improving our products. That being said, this bug tracking system is not a mechanism for requesting support, and we are not able to guarantee the timeliness or suitability of a resolution.
 
If this issue is critical or in any way time sensitive, please raise a ticket through the regular Red Hat support channels to ensure it receives the proper attention and prioritization to assure a timely resolution.
 
For information on how to contact the Red Hat production support team, please visit:
    https://access.redhat.com/support

Comment 6 RHEL Program Management 2021-08-26 07:27:10 UTC
After evaluating this issue, there are no plans to address it further or fix it in an upcoming release.  Therefore, it is being closed.  If plans change such that this issue will be fixed in an upcoming release, then the bug can be reopened.