[humanpuff69]

hi guys

so i just want to warn you all . there are a bug that will pretty much break your vps . i try the solution that the internet gives by googling but have no luck so i just reinstalled my vps but here how its done
what you need to do is install mysql by using "apt-get install mysql-server" and after that try to purge it . if you lucky enough it will create a dpkg error regarding the mysql-server-5.7 and you basically cannot uninstall it . i try all the tutorial even deleting all of my databse content but my server s still screwed . you cannot use your apt-get again (most application failed to install after you trigger this bug . some that does install spesifically that dosnt need mysql)
and after i search i got the cause of this problem it look like that it is a bug and i dont know if it already fixed but from my experience it is still here . i mean the bug
so just be careful . if you already installed mysql on your server that have 16.04 (i see 14.04 that get this bg as well so be careful) dont uninstall mysql-server otherwise your server will be screwed

Here is the thing that you will get if your server aready get screwed

Terminal

phpmyadmin is already the newest version (4:4.5.4.1-2ubuntu2).
0 upgraded, 0 newly installed, 0 to remove and 116 not upgraded.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up mysql-server-5.7 (5.7.19-0ubuntu0.16.04.1) ...
invoke-rc.d: policy-rc.d denied execution of stop.
/var/lib/dpkg/info/mysql-server-5.7.postinst: line 143: /usr/share/mysql-common/configure-symlinks: No such file or directory
dpkg: error processing package mysql-server-5.7 (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of mysql-server:
 mysql-server depends on mysql-server-5.7; however:
  Package mysql-server-5.7 is not configured yet.

dpkg: error processing package mysql-server (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 mysql-server-5.7
 mysql-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

and you think you can uninstall and then install it . WRONG you CANT . if you purge it and then install it again it will come back and even if you just uninstall it it will still be stuck there

Terminal

apt-get install mysql-server
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  libevent-core-2.0-5 mysql-server-5.7 mysql-server-core-5.7
Suggested packages:
  tinyca
The following NEW packages will be installed:
  libevent-core-2.0-5 mysql-server mysql-server-5.7 mysql-server-core-5.7
0 upgraded, 4 newly installed, 0 to remove and 116 not upgraded.
Need to get 7,658 kB/10.1 MB of archives.
After this operation, 94.8 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 mysql-server-core-5.7 amd64 5.7.19-0ubuntu0.16.04.1 [7,588 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libevent-core-2.0-5 amd64 2.0.21-stable-2ubuntu0.16.04.1 [70.6 kB]
Fetched 7,658 kB in 3s (2,418 kB/s)       
Preconfiguring packages ...
Selecting previously unselected package mysql-server-core-5.7.
(Reading database ... 90254 files and directories currently installed.)
Preparing to unpack .../mysql-server-core-5.7_5.7.19-0ubuntu0.16.04.1_amd64.deb ...
Unpacking mysql-server-core-5.7 (5.7.19-0ubuntu0.16.04.1) ...
Selecting previously unselected package libevent-core-2.0-5:amd64.
Preparing to unpack .../libevent-core-2.0-5_2.0.21-stable-2ubuntu0.16.04.1_amd64.deb ...
Unpacking libevent-core-2.0-5:amd64 (2.0.21-stable-2ubuntu0.16.04.1) ...
Selecting previously unselected package mysql-server-5.7.
Preparing to unpack .../mysql-server-5.7_5.7.19-0ubuntu0.16.04.1_amd64.deb ...
Unpacking mysql-server-5.7 (5.7.19-0ubuntu0.16.04.1) ...
Selecting previously unselected package mysql-server.
Preparing to unpack .../mysql-server_5.7.19-0ubuntu0.16.04.1_all.deb ...
Unpacking mysql-server (5.7.19-0ubuntu0.16.04.1) ...
Processing triggers for man-db (2.7.5-1) ...
Processing triggers for libc-bin (2.23-0ubuntu9) ...
Processing triggers for systemd (229-4ubuntu19) ...
Setting up mysql-server-core-5.7 (5.7.19-0ubuntu0.16.04.1) ...
Setting up libevent-core-2.0-5:amd64 (2.0.21-stable-2ubuntu0.16.04.1) ...
Setting up mysql-server-5.7 (5.7.19-0ubuntu0.16.04.1) ...
invoke-rc.d: policy-rc.d denied execution of stop.
/var/lib/dpkg/info/mysql-server-5.7.postinst: line 143: /usr/share/mysql-common/configure-symlinks: No such file or directory
dpkg: error processing package mysql-server-5.7 (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of mysql-server:
 mysql-server depends on mysql-server-5.7; however:
  Package mysql-server-5.7 is not configured yet.

dpkg: error processing package mysql-server (--configure):
 dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.23-0ubuntu9) ...
Processing triggers for systemd (229-4ubuntu19) ...
Errors were encountered while processing:
 mysql-server-5.7
 mysql-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

[kubanek_kuba]

Interesting, first time I see bug in Ubuntu which can cause that much problems with system. Its good to know about it because most of servers use mysql.

[xdude]

I have 2 servers which I have Ubuntu and VirtualMin on. I haven't noticed anything wrong yet. I think mysql is already installed with Ubuntu and then Webmin/Virtualmin install other support files. Anyway I will check everything again.

[oraldavid]

I have got this problem too, So I have reinstalled my VPS to resolve the issue.

[Honey]

Thanks for telling us about it, so far I haven't gotten any issue like that but I will be careful about it now

[humanpuff69]

reinstalling it fixes the problem . but it is kinda dangerous for high traffic serverbecause it can break the user experience

[deanhills]

I'm also very surprised. I'm with a Free VPS Host that has been offering Ubuntu as an OS option for a couple or more years now and haven't had any negative feedback about bugs yet. So probably good to be informed about it so I can refer back to this thread for further information if this should ever get to be reported. But for now this hasn't been an issue yet.

[humanpuff69]

I'm also very surprised. I'm with a Free VPS Host that has been offering Ubuntu as an OS option for a couple or more years now and haven't had any negative feedback about bugs yet. So probably good to be informed about it so I can refer back to this thread for further information if this should ever get to be reported. But for now this hasn't been an issue yet.

but for me and when i try sshing to my client that they want me to install something on their vps it have the same mysql error and the problem is that basically its bricked you cannot apt-get anything . for me reinstalling the vps is the best choice because i try using all the turoial on google and still no luck

[Kururin]

Well that's why I don't use any Ubuntu servers, Debian have been and will be my no #1 choice in terms of stability and bug-free mostly

[deanhills]

I'm sure the Ubuntu "bug" is a rare occurrence, otherwise Ubuntu wouldn't have had such a big following and hosts wouldn't have it loaded as a standard OS choice on all of their VPSs. My preference is CentOS as I use VPSs mostly for Webhosting, but I still think very highly of Ubuntu. Debian is very good too, but requires more experience to manage.