systemctl status mysqld.service shows activating

Question

I have configured MySQL 5.7.25 instance using Linux Generic Binaries on a separate mount point (instead of default locations) on a test server (RHEL 7.4).

The systemd support, in this case, must be manually configured, which I did.

My question is regarding the systemctl command.  When I issue systemctl status mysqld.service, the output shows "activating (start)" but the service is "started successfully" (at least I think so as per alert logs) and I don't get the prompt back. I have to Ctrl+C to get the prompt back. In the case of other services, systemctl status shows active (started). Also, systemctl status mysqld.service shows "PID file /usr/local/mysql/data/mysqld.pid not readable (yet?) after start."

The PID gets generated in the defined location as can be seen below in ls -l output.

How do I deal with this?

Following is the output of the systemctl status mysqld.service:

> [root@localhost system]# systemctl status mysqld.service ●
> mysqld.service - MySQL Server    Loaded: loaded
> (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset:
> disabled)    Active: **activating (start)** since Wed 2019-03-27
> 16:58:13 IST; 5min ago
>      Docs: man:mysqld(7)
>            http://dev.mysql.com/doc/refman/en/using-systemd.html   Process: 9307
> ExecStart=/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld
> --lc-messages-dir=/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/share
> --daemonize --pid-file=/mysql/mysql_data/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)    CGroup:
> /system.slice/mysqld.service
>            └─9309 /mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld
> --lc-messages-dir=/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/share
> --daemonize --pid-file=/mysql/mysql_data/...
> 
> Mar 27 16:58:13 localhost.localdomain systemd[1]: **Starting MySQL
> Server...** Mar 27 16:58:13 localhost.localdomain systemd[1]: **PID
> file /usr/local/mysql/data/mysqld.pid not readable (yet?) after
> start.** [root@localhost system]#

Following is the output of ls -l for the data directory.

[root@localhost mysql_data]# ls -l
total 122964
-rw-r-----. 1 mysql mysql       56 Mar 27 16:14 auto.cnf
-rw-r-----. 1 mysql mysql      283 Mar 27 16:58 ib_buffer_pool
-rw-r-----. 1 mysql mysql 12582912 Mar 27 16:58 ibdata1
-rw-r-----. 1 mysql mysql 50331648 Mar 27 16:58 ib_logfile0
-rw-r-----. 1 mysql mysql 50331648 Mar 27 16:13 ib_logfile1
-rw-r-----. 1 mysql mysql 12582912 Mar 27 16:58 ibtmp1
drwxr-x---. 2 mysql mysql     4096 Mar 27 16:14 mysql
-rw-r-----. 1 mysql mysql    41256 Mar 27 16:58 mysqld.log
-rw-r-----. 1 mysql mysql        5 Mar 27 16:58 mysqld.pid
srwxrwxrwx. 1 mysql mysql        0 Mar 27 16:58 mysql.sock
-rw-------. 1 mysql mysql        5 Mar 27 16:58 mysql.sock.lock
drwxr-x---. 2 mysql mysql     4096 Mar 27 16:14 performance_schema
drwxr-x---. 2 mysql mysql    12288 Mar 27 16:14 sys
[root@localhost mysql_data]# 

Following is the /usr/lib/systemd/system/mysqld.service file:

[root@localhost system]# cat mysqld.service
[Unit]
Description=MySQL
Server Documentation=man:mysqld(7)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target

[Install]
WantedBy=multi-user.target

[Service] 
User=mysql
Group=mysql

Type=forking

PIDFile=/usr/local/mysql/data/mysqld.pid

# Disable service start and stop timeout logic of systemd for mysqld service. 
TimeoutSec=0

# Start main service
ExecStart=/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld --lc-messages-dir=/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/share --daemonize --pid-file=/mysql/mysql_data/mysqld.pid $MYSQLD_OPTS 

# Use this to switch malloc implementation
EnvironmentFile=-/etc/sysconfig/mysql

# Sets open_files_limit
LimitNOFILE = infinity

Restart=on-failure

RestartPreventExitStatus=1

PrivateTmp=false
[root@localhost system]#

       ^{Warning: The above file contents were manually reconstructed after being corrupted.}

Following is the alert log file which shows that mysqld is ready for connections.

2019-03-27T11:28:13.334048Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2019-03-27T11:28:13.335294Z 0 [Note] /mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld (mysqld 5.7.25) starting as process 9309 ...
2019-03-27T11:28:13.337926Z 0 [Note] InnoDB: PUNCH HOLE support available
2019-03-27T11:28:13.337953Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2019-03-27T11:28:13.337959Z 0 [Note] InnoDB: Uses event mutexes
2019-03-27T11:28:13.337964Z 0 [Note] InnoDB: GCC builtin __sync_synchronize() is used for memory barrier
2019-03-27T11:28:13.337969Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.11
2019-03-27T11:28:13.337974Z 0 [Note] InnoDB: Using Linux native AIO
2019-03-27T11:28:13.338216Z 0 [Note] InnoDB: Number of pools: 1
2019-03-27T11:28:13.338317Z 0 [Note] InnoDB: Using CPU crc32 instructions
2019-03-27T11:28:13.339746Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
2019-03-27T11:28:13.351813Z 0 [Note] InnoDB: Completed initialization of buffer pool
2019-03-27T11:28:13.353463Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
2019-03-27T11:28:13.365875Z 0 [Note] InnoDB: Highest supported file format is Barracuda.
2019-03-27T11:28:13.380701Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2019-03-27T11:28:13.380772Z 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2019-03-27T11:28:13.417750Z 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.
2019-03-27T11:28:13.418493Z 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active.
2019-03-27T11:28:13.418503Z 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active.
2019-03-27T11:28:13.418713Z 0 [Note] InnoDB: Waiting for purge to start
2019-03-27T11:28:13.472045Z 0 [Note] InnoDB: 5.7.25 started; log sequence number 2524297
2019-03-27T11:28:13.472824Z 0 [Note] InnoDB: Loading buffer pool(s) from /mysql/mysql_data/ib_buffer_pool
2019-03-27T11:28:13.473297Z 0 [Note] Plugin 'FEDERATED' is disabled.
2019-03-27T11:28:13.474439Z 0 [Note] InnoDB: Buffer pool(s) load completed at 190327 16:58:13
2019-03-27T11:28:13.478030Z 0 [Warning] Failed to set up SSL because of the following SSL library error: SSL context is not usable without certificate and private key
2019-03-27T11:28:13.478659Z 0 [Note] Server hostname (bind-address): '*'; port: 3306
2019-03-27T11:28:13.478711Z 0 [Note] IPv6 is available.
2019-03-27T11:28:13.478724Z 0 [Note]   - '::' resolves to '::';
2019-03-27T11:28:13.478745Z 0 [Note] Server socket created on IP: '::'.
2019-03-27T11:28:13.489601Z 0 [Note] Event Scheduler: Loaded 0 events
2019-03-27T11:28:13.489791Z 0 [Note] **/mysql/mysql_install/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld: ready for connections.**
Version: '5.7.25'  socket: '/mysql/mysql_data/mysql.sock'  port: 3306  MySQL Community Server (GPL)

I have tried the same procedure twice with same issue. The systemctl status mysqld.service shows "activating (start)" and does not return the prompt. I can log in to the database.

Answer 1

From your output:

ExecStart=...mysqld ... --pid-file=/mysql/mysql_data/mysqld.pid ...

... does not match what you're asking systemd to watch:

PIDFile=/usr/local/mysql/data/mysqld.pid

correct one of those two, and you'll be in much better shape.