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Resolved ERROR: PleskDBException: Unable to connect to database: mysql_connect():

daanse

Regular Pleskian
Hi,

i'm using: "12.5.30 Update #23, zuletzt aktualisiert: 25. Febr. 2016 23:00:41" and today it seems that Plesk updated automatically (turned it off just in case now) and everything was down:

ERROR: PleskDBException: Unable to connect to database: mysql_connect(): Resource temporarily unavailable /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible. (Abstract.php:69)

after that, i made a restart.

ERROR: PleskDBException: Unable to connect to database: mysql_connect(): No such file or directory /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible. (Abstract.php:69)

in meanwhile ...

Error displaying the error page: Application Instantiation Error: Could not connect to MySQL.

Current Status after restart...

What can i do against this? It's really annoying. This happened 10 Times the last Year always at round about 7 o' clock (Germany)... My Customers will kill me the next time this happends..

The Solution for the moment was to hit "/etc/init.d/apache2 restart" in SSH..

Any Leads or How To's or Answers would be great.
 
How can i check? Which command do i need to run?
I'm using Debian 8.3
But on two other Servers i got this Problem last Year over 10 Times. There i had Cent OS and always Latest Version.
 
HI,
Thank you.

"/var/log/mysqld.log" is empty. No Errors.

Maybe its related to the recently activated Firewall Settings? Could this cause such a Problem?
 
Have you tried to restart mysql service at least?
 
Yes. Its okay now but i'm afraid about the next Update. I turned off "automatic Update" but i got to a Point where i want to figure out the Causes...
I had this really often with different Servers in the Past.
I think i am missing something.

What i know, one Server without Firewall active (don't know why it was deactivated) there where no Problems.
 
I still have these Errors for 1-5 Minutes in the morning and then its fine again.
What can i do?
 
again this morning. :-( Really need help here.
whis is something i could get out

Code:
systemctl status mysql.service
● mysql.service - LSB: Start and stop the mysql database server daemon
   Loaded: loaded (/etc/init.d/mysql)
   Active: failed (Result: exit-code) since Sun 2016-03-06 07:22:15 CET; 11s ago
  Process: 26652 ExecStop=/etc/init.d/mysql stop (code=exited, status=1/FAILURE)
  Process: 26695 ExecStart=/etc/init.d/mysql start (code=exited, status=1/FAILURE)

Mar 06 07:21:44 my-domain.com /etc/init.d/mysql[26722]: 160306 0...
Mar 06 07:22:15 my-domain.com mysql[26695]: Starting MariaDB dat...
Mar 06 07:22:15 my-domain.com systemd[1]: mysql.service: control...
Mar 06 07:22:15 my-domain.com systemd[1]: Failed to start LSB: S...
Mar 06 07:22:15 my-domain.com systemd[1]: Unit mysql.service ent...
Hint: Some lines were ellipsized, use -l to show in full.
root@web-host04 ~ # systemctl status mysql.service -l
● mysql.service - LSB: Start and stop the mysql database server daemon
   Loaded: loaded (/etc/init.d/mysql)
   Active: failed (Result: exit-code) since Sun 2016-03-06 07:22:15 CET; 19s ago
  Process: 26652 ExecStop=/etc/init.d/mysql stop (code=exited, status=1/FAILURE)
  Process: 26695 ExecStart=/etc/init.d/mysql start (code=exited, status=1/FAILURE)

Mar 06 07:21:44 my-domain.com /etc/init.d/mysql[26722]: 160306 07:21:44 mysqld_safe A mysqld process already exists
Mar 06 07:22:15 my-domain.com mysql[26695]: Starting MariaDB database server: mysqld . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . failed!
Mar 06 07:22:15 my-domain.com systemd[1]: mysql.service: control process exited, code=exited status=1
Mar 06 07:22:15 my-domain.com systemd[1]: Failed to start LSB: Start and stop the mysql database server daemon.
Mar 06 07:22:15 my-domain.com systemd[1]: Unit mysql.service entered failed state.
root@web-host04 ~ # service apache2 restart
root@web-host04 ~ # etc/init.d/mysqld restart
-bash: etc/init.d/mysqld: No such file or directory
root@web-host04 ~ # service mysql restart
Job for mysql.service failed. See 'systemctl status mysql.service' and 'journalctl -xn' for details.
root@web-host04 ~ # service pache restart
Failed to restart pache.service: Unit pache.service failed to load: No such file or directory.
root@web-host04 ~ #

and i found under "Trouble Shooter - Protocol Search" following:
Code:
18: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:131
    CommonPanel_Application_Abstract->_initTranslate()
19: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:39
    CommonPanel_Application_Abstract->run()
20: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:18
    CommonPanel_Application_Abstract::init()
21: /opt/psa/admin/plib/pm/Bootstrap.php:15
    pm_Bootstrap::init()
22: /opt/psa/admin/plib/sdk.php:12
[2016-03-06 06:30:03] ERR [1] SQLSTATE[HY000]: General error: 23 Out of resources when opening file '/tmp/#sql_459_1.MAI' (Errcode: 24 "Too many open files")
[2016-03-06 07:05:01] ERR [panel] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.:
0: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:69
    CommonPanel_Application_Abstract::initDbAdapter()
1: /opt/psa/admin/plib/Session/Helper.php:150
    Plesk\Session\Helper::initStorage()
2: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:36
    CommonPanel_Application_Abstract->run()
3: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:18
    CommonPanel_Application_Abstract::init()
4: /opt/psa/admin/plib/pm/Bootstrap.php:15
    pm_Bootstrap::init()
5: /opt/psa/admin/plib/sdk.php:12
[2016-03-06 07:05:01] ERR [1] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.
[2016-03-06 07:10:01] ERR [panel] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.:
0: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:69
    CommonPanel_Application_Abstract::initDbAdapter()
1: /opt/psa/admin/plib/Session/Helper.php:150
    Plesk\Session\Helper::initStorage()
2: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:36
    CommonPanel_Application_Abstract->run()
3: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:18
    CommonPanel_Application_Abstract::init()
4: /opt/psa/admin/plib/pm/Bootstrap.php:15
    pm_Bootstrap::init()
5: /opt/psa/admin/plib/sdk.php:12
[2016-03-06 07:10:01] ERR [panel] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.:
0: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:69
    CommonPanel_Application_Abstract::initDbAdapter()
1: /opt/psa/admin/plib/Session/Helper.php:150
    Plesk\Session\Helper::initStorage()
2: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:36
    CommonPanel_Application_Abstract->run()
3: /opt/psa/admin/plib/CommonPanel/Application/Abstract.php:18
    CommonPanel_Application_Abstract::init()
4: /opt/psa/admin/plib/pm/Bootstrap.php:15
    pm_Bootstrap::init()
5: /opt/psa/admin/plib/sdk.php:12
[2016-03-06 07:10:01] ERR [1] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.
[2016-03-06 07:10:01] ERR [1] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.
[2016-03-06 07:10:34] ERR [panel] Unable to connect to database:  /var/run/mysqld/mysqld.sock (Error code: 2002). Please check that database server is started and accessible.:
...... and 100 Lines more

i think the First line is my Problem: [2016-03-06 06:30:03] ERR [1] SQLSTATE[HY000]: General error: 23 Out of resources when opening file '/tmp/#sql_459_1.MAI' (Errcode: 24 "Too many open files") ????
After this the Server was down i think?

Does this helps?
Code:
root@web-host04 ~ # ulimit -Hn
65536
root@web-host04 ~ # ulimit -Sn
65536
root@web-host04 ~ # ulimit -a
core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 257438
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 65536
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 257438
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited
root@web-host04 ~ #
 
Last edited:
Hi, view the Log.
if its say somewhere "too many files open" its about changing MySQL Setting "open Files Limit"
This and gracefully restart worked always for me.
Actually i never had Problems again (after increasing Value)
 
Yes I think it's the same probleme, but I doesn't have the open_limit_file on /etc/mysql/my.conf. And I don't know where is it !
I'm on Debian 8.0‬ - Plesk 12.5.30.

On my.conf :
Code:
!includedir /etc/mysql/conf.d/
[mysqld]
#bind-address = ::
bind-address = **.*.*.*
skip_name_resolve
local-infile=0

On my /etc/security/limits.conf :
Code:
#*               soft    core            0
#root            hard    core            100000
#*               hard    rss             10000
#@student        hard    nproc           20
#@faculty        soft    nproc           20
#@faculty        hard    nproc           50
#ftp             hard    nproc           0
#ftp             -       chroot          /ftp
#@student        -       maxlogins       4
When i did "mysql -uadmin -p`cat /etc/psa/.psa.shadow` psa -e "SHOW VARIABLES LIKE 'Open_files_limit';" : I show : 1024 and I know I must Increase this values, but i don't know where !
 
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