Troubleshooting
Problem
IBM HTTP Server (or any Web server) fails to start. It reports a port 80 conflict.
Symptom
When starting an IBM HTTP Server that listens on port 80, the user gets the following error:
address already in use. make_sock: could not bind to address [::]:80 no listening sockets available.
Cause
Starting with AIX 5.3 TL09 and AIX 6.1.3.0, it automatically starts LWI http server as WebSM server. The http4websm subsystem is bound to port 80.
Even after the server reboot, port 80 will be bound to http4websm subsystem. This conflicts with IBM HTTP Server that also listens on port 80. Thus IBM HTTP Server fails to start.
Environment
AIX 6100 TL4, 6100 TL3, 6100 TL2 SP4, 5300 TL11, 5300 TL10, and 5300 TL9 SP4
Diagnosing The Problem
Before starting IBM HTTP Server, issue the following request:
http://hostname
If you see the AIX Web-based System Manager page, you will have the problem.
Resolving The Problem
The AIX team has APARs for this problem. (Different APAR numbers for different TLs.) Before the fix is applied, you can manually comment out the following line in the /etc/inittab file:
webserverstart:2:once:startsrc -s http4websm
For more details about AIX APARs, see the links to "Fix pack information for: port 80 address already in use" below.
Note: The idea of checking port conflict as described in this technote is not limited to WebSM. If any component, such as a Proxy server, is listening on port 80, IBM HTTP Server won't start if it also listens on port 80.
Related Information
Was this topic helpful?
Document Information
Modified date:
07 September 2022
UID
swg21390267