Linux Tips, Tricks, Tutorials & Fixes

Sometimes, our databases got corrupted and innoDB crashed in the server. Due to this, MySQL service won't restart and following message: Starting MySQL..The server quit without updating PID file (/var/lib/mysql/my.server.com.pid).[FAILED] or MySQL server PID file could not be found! In such situation, you will have to start MySQL with InnoDB in force recovery mode using the following steps: Step 1. Stop MySQL service Step 2. Backup /var/lib/mysql directory Step 3. Add the following line into /etc/my.cnf: innodb_force_recovery = 4 Step 4: Restart MySQL. Your database will now start, but with innodb_force_recovery, all INSERTs and UPDATEs will be ignored. Step 5: Dump all tables Step 6: Shutdown database and delete the data directory. Run mysql_install_db to create MySQL default tables Step 7: Remove the innodb_force_recovery line from your /etc/my.cnf file and restart the database. (It should start normally now) Step 8: Restore everything from your backup

Issue: You get the following error while accessing your email account: 2014-09-08 14:03:43 dovecot_plain authenticator failed for ([127.0.0.1]) [IP ADDRESS]:59278 I=[IP ADDRESS]:465: 535 Incorrect authentication data (set_id=email@domain_name) Fix: Users with root access can fix this problem through WHM using the following steps: 1. Login to WHM 2. Locate the Email section in the left-side panel 3. Select Repair Mailbox permissions 4. Click Proceed.  

Issue: MySQL is not reatsrting in the server. You get the following error: Starting MySQL...... ERROR! The server quit without updating PID file (/var/lib/mysql/server.hostname.pid) ERROR! MySQL is not running, but lock file (/var/lock/subsys/mysql) exists Fix: This likely indicates that native AIO support is not enabled on the server. Add the following line to /etc/my.cnf and MySQL should then restart successfully: Code: innodb_use_native_aio = 0

Issue: Sometimes, you get 404 error in the browser while executing perl script hosted under cPanel server. Fix: The 404 errors may occur for perl script because of the domain doesn't have CGI enabled for the account. You can check the same using the following command: [root@server]# grep HASCGI /var/cpanel/users/username* HASCGI=0 ^ In order to fix this issue for that user, you should be able to modify the HASCGI value in the file "/var/cpanel/users/username*" to 1 and then run /scripts/updateuserdomains and then /scripts/rebuildhttpdconf P.S: Replace username with your actual user of the domain.