Bug 867467

Summary:	httpd restart fails for 2 consecutive restarts
Product:	Red Hat Enterprise Linux 6	Reporter:	Martin Kosek <mkosek>
Component:	httpd	Assignee:	Luboš Uhliarik <luhliari>
Status:	CLOSED NEXTRELEASE	QA Contact:	BaseOS QE Security Team <qe-baseos-security>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	6.4	CC:	jorton
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-10-17 15:18:56 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:
Bug Depends On:
Bug Blocks:	845405

Description Martin Kosek 2012-10-17 14:55:32 UTC

Description of problem:
When IPA replica install process does 2 consecutive httpd restarts, the second httpd restart may fail and thus IPA replica installation will fail.

See Bug 845405 for details.

Version-Release number of selected component (if applicable):
httpd-2.2.15-19.el6.x86_64

How reproducible:
I think I managed to reproduce it with this simple sequence:

# service httpd restart && service httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                            [  OK  ]
Stopping httpd:                                            [FAILED]
Starting httpd: (98)Address already in use: make_sock: could not bind to address [::]:80
(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs
                                                           [FAILED]

When I tested this sequence on Fedora 18, it worked fine. It just probably waited until the ports could be bound.

Steps to Reproduce:
1. See above - run  2 consecutive service restarts
2.
3.
  
Actual results:
Second restart fails.

Expected results:
Second restart succeeds.

Additional info:

Comment 2 Joe Orton 2012-10-17 15:18:56 UTC

The answer is "Don't do that", I'm afraid.

With the sysV init scripts we can't make a strong guarantee that httpd is immediately in a state where the service script will always DTRT.  Adding a sleep(1) or similar should help, but if you are loading weird modules like mod_nss with complex startup processing, you might need more than 1 second delay.

With systemd we do make a strong guarantee and this kind of thing really works properly.