[solved] Mailserver - "insufficient system storage" || Increasing Diskspace?

Servus! Sorry, but I noobishly require help again:
Ubuntu 18.04 on a Hyper-V machine with 15GB HDD (little low, turned it up, see below)
Maillogs state "Insufficient System Storage".

"df":

Code:

Filesystem                        1K-blocks    Used Available Use% Mounted on
udev                                 435136       0    435136   0% /dev
tmpfs                                 93152    1008     92144   2% /run
/dev/mapper/ubuntu--vg-ubuntu--lv   4062912 3826956      9860 100% /
tmpfs                                465760       0    465760   0% /dev/shm
tmpfs                                  5120       0      5120   0% /run/lock
tmpfs                                465760       0    465760   0% /sys/fs/cgroup
/dev/loop0                            93184   93184         0 100% /snap/core/6350
/dev/sda2                            999320   76940    853568   9% /boot
tmpfs                                 93152       0     93152   0% /run/user/1000

I don't quite understand the /dev/mapper/ubuntu--vg[...] part and why it is full. :/

"fdisk -l":

Code:

Disk /dev/loop0: 91 MiB, 95408128 bytes, 186344 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes




GPT PMBR size mismatch (31457279 != 104857599) will be corrected by w(rite).
Disk /dev/sda: 50 GiB, 53687091200 bytes, 104857600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: D444AFBC-006C-49F3-8D57-7F6C7B621906

Device       Start      End  Sectors Size Type
/dev/sda1     2048     4095     2048   1M BIOS boot
/dev/sda2     4096  2101247  2097152   1G Linux filesystem
/dev/sda3  2101248 31455231 29353984  14G Linux filesystem

Now I turned up the virtual HDDspace to 50GB in Hyper-V. My question now is: which sda should I increase? Via fdisk or via lvextend?

 

I have used systemrescuecd http://www.system-rescue-cd.org/. Boot the virtual host from that and use it to resize the file system.

 

Thanks to the both of you. I will look/read into it and report back when I got to it.
Backing up the vHDD was the first thing I did before changing the size in Hyper-V. I seem to learn.

 

Problem solved.
That solution lead to another problem (classic hydra): Dovecot can't start because mysql is not working/starting.

Code:

root@web:/# service mysql restart
Job for mariadb.service failed because the control process exited with error code.
See "systemctl status mariadb.service" and "journalctl -xe" for details.
root@web:/# service mysql status
● mariadb.service - MariaDB 10.1.38 database server
   Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Thu 2019-03-21 16:05:41 UTC; 15s ago
     Docs: man:mysqld(8)
           https://mariadb.com/kb/en/library/systemd/
  Process: 3220 ExecStart=/usr/sbin/mysqld $MYSQLD_OPTS $_WSREP_NEW_CLUSTER $_WSREP_START_POSITION (code=exited, status=1/FAILURE)
  Process: 3147 ExecStartPre=/bin/sh -c [ ! -e /usr/bin/galera_recovery ] && VAR= ||   VAR=`/usr/bin/galera_recovery`; [ $? -eq 0 ]   && systemctl set-environment _WSREP_START_POSITION=$VAR
  Process: 3140 ExecStartPre=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)
  Process: 3128 ExecStartPre=/usr/bin/install -m 755 -o mysql -g root -d /var/run/mysqld (code=exited, status=0/SUCCESS)
 Main PID: 3220 (code=exited, status=1/FAILURE)
   Status: "MariaDB server is down"

Mar 21 16:05:38 web systemd[1]: Starting MariaDB 10.1.38 database server...
Mar 21 16:05:38 web mysqld[3220]: 2019-03-21 16:05:38 139957119171712 [Note] /usr/sbin/mysqld (mysqld 10.1.38-MariaDB-0ubuntu0.18.04.1) starting as process 3220 ...
Mar 21 16:05:41 web systemd[1]: mariadb.service: Main process exited, code=exited, status=1/FAILURE
Mar 21 16:05:41 web systemd[1]: mariadb.service: Failed with result 'exit-code'.
Mar 21 16:05:41 web systemd[1]: Failed to start MariaDB 10.1.38 database server.
lines 1-17/17 (END)
root@web:/# service mysql reload
 * Reloading MariaDB database server mysqld                                                                                                                                                  /usr/bin/mysqladmin: connect to server at 'localhost' failed
error: 'Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2 "No such file or directory")'
Check that mysqld is running and that the socket: '/var/run/mysqld/mysqld.sock' exists!

mysqld.sock does of course not exist. Would redoing Step6 of the perfect server Tutorial fix this?

 

Thanks, that was the file I was looking for.

Code:

Mar 21 17:38:06 web systemd[1]: Starting MariaDB 10.1.38 database server...
Mar 21 17:38:06 web mysqld[17332]: 2019-03-21 17:38:06 140569265572992 [Note] /usr/sbin/mysqld (mysqld 10.1.38-MariaDB-0ubuntu0.18.04.1) starting as process 17332 ...
Mar 21 17:38:09 web systemd[1]: mariadb.service: Main process exited, code=exited, status=1/FAILURE
Mar 21 17:38:09 web systemd[1]: mariadb.service: Failed with result 'exit-code'.
Mar 21 17:38:09 web systemd[1]: Failed to start MariaDB 10.1.38 database server.

I feel like that wasn't very helpful.

 

Except for loop0 (100%) everything is below 10% usage now. In "ls -l /dev/" every sda has the same permissions/owner/group.

 

That's an error mssg I found and posted earlier. I don't know if solving it would solve my issue.

EDIT:

Code:

root@web:/#  mysqlcheck -u root -p --all-databases --optimize --auto-repair
Enter password:
mysqlcheck: Got error: 2002: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2 "No such file or directory") when trying to connect

EDIT2: found a "/var/log/mysql/error.log":

Code:

2019-03-22  0:49:00 140418422365312 [Note] InnoDB: innodb_empty_free_list_algorithm has been changed to legacy because of small buffer pool size. In order to use backoff, increase buffer pool at least up to 20MB.

2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Using mutexes to ref count buffer pool pages
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: The InnoDB memory heap is disabled
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Compressed tables use zlib 1.2.11
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Using Linux native AIO
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Using SSE crc32 instructions
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Completed initialization of buffer pool
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Highest supported file format is Barracuda.
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: 128 rollback segment(s) are active.
2019-03-22  0:49:00 140418422365312 [Note] InnoDB: Waiting for purge to start
2019-03-22  0:49:01 140418422365312 [Note] InnoDB:  Percona XtraDB (http://www.percona.com) 5.6.42-84.2 started; log sequence number 3159781
2019-03-22  0:49:01 140418422365312 [Note] Plugin 'FEEDBACK' is disabled.
2019-03-22  0:49:01 140418422365312 [Note] Recovering after a crash using tc.log
2019-03-22  0:49:01 140418422365312 [ERROR] Can't init tc log
2019-03-22  0:49:01 140418422365312 [ERROR] Aborting

SOLVED: https://fransdejonge.com/2018/02/mariadb-fix-cant-init-tc-log-error/

 

This is hopefully my last post for now. Everything seems to work (for) now.

In the end, I still had an error, which I solved with the marked answer in this thread: https://stackoverflow.com/questions/18377813/postfix-status-bounced-unknown-user-myuser

Thanks for all the help and patience!