1. Please take a little time for this simple survey! Thank you for participating!
    Dismiss Notice
  2. Dear Pleskians, please read this carefully! New attachments and other rules Thank you!
    Dismiss Notice
  3. Dear Pleskians, I really hope that you will share your opinion in this Special topic for chatter about Plesk in the Clouds. Thank you!
    Dismiss Notice

Watchdog and MySQL

Discussion in 'Plesk 10.x for Linux Issues, Fixes, How-To' started by MassimoP, Nov 11, 2010.

  1. MassimoP

    MassimoP Basic Pleskian

    17
    35%
    Joined:
    Aug 13, 2010
    Messages:
    39
    Likes Received:
    0
    For a strange reason, after a reboot the Watchdog module does not recognize the mysql process (even if it is started and it is working) and tries to restart it.
    Actually a new mysql process is started thus blocking mysql, the following lines appear in the mysql log file:

    InnoDB: Unable to lock ./ibdata1, error: 11
    InnoDB: Check that you do not already have another mysqld process
    InnoDB: using the same InnoDB data or log files.

    After this point, mysql stops to accept connections.

    I don't understand why, but it is a weird behaviour of the mysql script which usually does not start another service instance.

    The sequence of operations is:
    1) start mysql at boot, it works perfectly
    2) watchdog checks mysql, does not recognize its presence and tries to restart it
    3) mysql start a new instance that block connections

    any idea?
     
  2. IgorG

    IgorG Forums Analyst Staff Member

    49
    24%
    Joined:
    Oct 27, 2009
    Messages:
    24,572
    Likes Received:
    1,243
    Location:
    Novosibirsk, Russia
    Check in /usr/local/psa/etc/modules/watchdog/monitrc that path to MySQL pid file is correct.
     
  3. MassimoP

    MassimoP Basic Pleskian

    17
    35%
    Joined:
    Aug 13, 2010
    Messages:
    39
    Likes Received:
    0
    Thanks, I checked the path to the pid file and it is correct...

    The problem arises only after a reboot.
     
  4. MassimoP

    MassimoP Basic Pleskian

    17
    35%
    Joined:
    Aug 13, 2010
    Messages:
    39
    Likes Received:
    0
    Just to add some information... The problem does not arise if the wathdog is disabled...
     
  5. MassimoP

    MassimoP Basic Pleskian

    17
    35%
    Joined:
    Aug 13, 2010
    Messages:
    39
    Likes Received:
    0
    Main caracteristics of the server in which I have this problem are
    CPU AuthenticAMD, Quad-Core AMD Opteron(tm) Processor 2372 HE
    Version Parallels Plesk Panel v10.0.1_build109101029.19 os_SuSE 11.1
    OS Linux 2.6.27.54-0.1-pae
     
    Last edited: Nov 16, 2010
  6. Justin Clarke

    Justin Clarke Regular Pleskian

    22
    40%
    Joined:
    Mar 3, 2010
    Messages:
    117
    Likes Received:
    0
    I am using Monit (instead of the built-in Watchdog) and this does exactly the same thing! I have to setup Monit on an alert only basis for MySQL otherwise it breaks when it tries to restart that process.

    Every time I start the Monit process (either manually or by rebooting my server) I get an alert from Monit saying that:

    Connection failed Service mysql

    Date: Thu, 18 Nov 2010 13:40:27 +0000
    Action: alert
    Host: myserver.info
    Description: failed, cannot open a connection to INET[127.0.0.1:3306] via TCP

    Your faithful employee,
    Monit
     
  7. MassimoP

    MassimoP Basic Pleskian

    17
    35%
    Joined:
    Aug 13, 2010
    Messages:
    39
    Likes Received:
    0
    I think that Whatdog and Monit are the same software...

    As requested by the forum moderator, please post your server main information, in this way a resolution of this bug could be faster.
     
  8. Justin Clarke

    Justin Clarke Regular Pleskian

    22
    40%
    Joined:
    Mar 3, 2010
    Messages:
    117
    Likes Received:
    0
    Plesk Parallels Panel v10.0.1

    CentOS - Linux 2.6.9-023stab052.4-smp

    VPS running AuthenticAMD, Quad-Core AMD Opteron(tm) Processor 2352

    1GB RAM (my share)

    10GB HDD (my share)
     
  9. German Wider

    German Wider Guest

    0
     
    Hi! Have you had any luck solving the problem? Same issue here.
     
  10. BenjS

    BenjS Guest

    0
     
    Same here with Debian 6.0 and Plesk 10.2.
    On every reboot, something wants to start a second mysql process. When I stop all mysql processes and start it again, it works.

    Any solution?
     
Loading...