Introduction
The error “No space left on device: Couldn’t create accept lock” in Apache usually indicates that system semaphore limits are exhausted. This can be resolved by clearing unused semaphores and increasing kernel limits.
Prerequisites
- Root SSH access to the server
- Basic knowledge of Linux commands
- Access to system configuration files
Implementation
Step 1: Remove unused semaphores
for semid in ipcs -s | grep apachec | cut -f2 -d” “; do ipcrm -s $semid; done
Step 2: Check current limits
ipcs -l
Step 3: Edit kernel parameters
vi /etc/sysctl.conf
Add or update the following values:
kernel.msgmni = 1024
kernel.sem = 250 256000 32 1024
Step 4: Apply changes
sysctl -p
Conclusion
By clearing unused semaphores and increasing kernel limits, you can resolve the Apache accept lock error and ensure stable server performance.