Summary
I installed Mattermost fresh (member server). I cant login after the succesfull setup and docker ps shows the container is “unhealthy”
I tried all kind of login credentials (a/Administrato with default pw + reinstalled with setting own password). Nothing seems to work.
The /var/log/mysql/error.log shows (last lines maybe interesting)
2020-05-01T11:12:50.445183Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-05-01T11:12:50.646697Z 0 [Warning] InnoDB: New log files created, LSN=45790
2020-05-01T11:12:50.699120Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2020-05-01T11:12:50.754747Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: b21bceef-8b9c-11ea-8199-0242ac110002.
2020-05-01T11:12:50.755833Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2020-05-01T11:12:50.932547Z 0 [Warning] CA certificate ca.pem is self signed.
2020-05-01T11:12:50.979951Z 1 [Warning] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.
2020-09-03T04:01:05.553056Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-09-03T04:01:05.917580Z 0 [Warning] InnoDB: New log files created, LSN=45790
2020-09-03T04:01:05.963502Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2020-09-03T04:01:06.030568Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 17535688-ed9a-11ea-8135-0242ac110004.
2020-09-03T04:01:06.032598Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2020-09-03T04:01:06.342784Z 0 [Warning] CA certificate ca.pem is self signed.
2020-09-03T04:01:06.471297Z 1 [Warning] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.
2020-09-03T04:01:11.185514Z mysqld_safe Logging to '/var/log/mysql/error.log'.
2020-09-03T04:01:11.210315Z mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
2020-09-03T04:01:11.429129Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-09-03T04:01:11.431429Z 0 [Note] /usr/sbin/mysqld (mysqld 5.7.29-0ubuntu0.16.04.1) starting as process 499 ...
2020-09-03T04:01:11.436919Z 0 [Note] InnoDB: PUNCH HOLE support available
2020-09-03T04:01:11.437003Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2020-09-03T04:01:11.437025Z 0 [Note] InnoDB: Uses event mutexes
2020-09-03T04:01:11.437043Z 0 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
2020-09-03T04:01:11.437059Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.8
2020-09-03T04:01:11.437078Z 0 [Note] InnoDB: Using Linux native AIO
2020-09-03T04:01:11.437392Z 0 [Note] InnoDB: Number of pools: 1
2020-09-03T04:01:11.437566Z 0 [Note] InnoDB: Using CPU crc32 instructions
2020-09-03T04:01:11.439859Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
2020-09-03T04:01:11.449741Z 0 [Note] InnoDB: Completed initialization of buffer pool
2020-09-03T04:01:11.453067Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
2020-09-03T04:01:11.467465Z 0 [Note] InnoDB: Highest supported file format is Barracuda.
2020-09-03T04:01:11.483919Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2020-09-03T04:01:11.484026Z 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2020-09-03T04:01:11.523270Z 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.
2020-09-03T04:01:11.524811Z 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active.
2020-09-03T04:01:11.524868Z 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active.
2020-09-03T04:01:11.525764Z 0 [Note] InnoDB: 5.7.29 started; log sequence number 2629923
2020-09-03T04:01:11.526061Z 0 [Note] InnoDB: Loading buffer pool(s) from /var/lib/mysql/ib_buffer_pool
2020-09-03T04:01:11.526338Z 0 [Note] Plugin 'FEDERATED' is disabled.
2020-09-03T04:01:11.529829Z 0 [Note] InnoDB: Buffer pool(s) load completed at 200903 4:01:11
2020-09-03T04:01:11.541044Z 0 [Note] Found ca.pem, server-cert.pem and server-key.pem in data directory. Trying to enable SSL support using them.
2020-09-03T04:01:11.541094Z 0 [Note] Skipping generation of SSL certificates as certificate files are present in data directory.
2020-09-03T04:01:11.541767Z 0 [Warning] CA certificate ca.pem is self signed.
2020-09-03T04:01:11.541818Z 0 [Note] Skipping generation of RSA key pair as key files are present in data directory.
2020-09-03T04:01:11.541928Z 0 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
2020-09-03T04:01:11.541984Z 0 [Note] - '0.0.0.0' resolves to '0.0.0.0';
2020-09-03T04:01:11.542030Z 0 [Note] Server socket created on IP: '0.0.0.0'.
2020-09-03T04:01:11.552455Z 0 [Note] Event Scheduler: Loaded 0 events
2020-09-03T04:01:11.552870Z 0 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.7.29-0ubuntu0.16.04.1' socket: '/var/run/mysqld/mysqld.sock' port: 3306 (Ubuntu)
2020-09-03T04:01:11.973948Z 2 [Note] Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)
2020-09-03T04:01:11.994316Z 3 [Note] Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)
2020-09-03T04:01:22.089991Z 0 [Note] Giving 0 client threads a chance to die gracefully
2020-09-03T04:01:22.090075Z 0 [Note] Shutting down slave threads
2020-09-03T04:01:22.090094Z 0 [Note] Forcefully disconnecting 0 remaining clients
2020-09-03T04:01:22.090113Z 0 [Note] Event Scheduler: Purging the queue. 0 events
2020-09-03T04:01:22.090195Z 0 [Note] Binlog end
2020-09-03T04:01:22.090980Z 0 [Note] Shutting down plugin 'ngram'
2020-09-03T04:01:22.091060Z 0 [Note] Shutting down plugin 'partition'
2020-09-03T04:01:22.091078Z 0 [Note] Shutting down plugin 'BLACKHOLE'
2020-09-03T04:01:22.091094Z 0 [Note] Shutting down plugin 'ARCHIVE'
2020-09-03T04:01:22.091110Z 0 [Note] Shutting down plugin 'CSV'
2020-09-03T04:01:22.091125Z 0 [Note] Shutting down plugin 'INNODB_SYS_VIRTUAL'
2020-09-03T04:01:22.091141Z 0 [Note] Shutting down plugin 'INNODB_SYS_DATAFILES'
2020-09-03T04:01:22.091155Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLESPACES'
2020-09-03T04:01:22.091170Z 0 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN_COLS'
2020-09-03T04:01:22.091184Z 0 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN'
2020-09-03T04:01:22.091198Z 0 [Note] Shutting down plugin 'INNODB_SYS_FIELDS'
2020-09-03T04:01:22.091212Z 0 [Note] Shutting down plugin 'INNODB_SYS_COLUMNS'
2020-09-03T04:01:22.091225Z 0 [Note] Shutting down plugin 'INNODB_SYS_INDEXES'
2020-09-03T04:01:22.091239Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLESTATS'
2020-09-03T04:01:22.091253Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLES'
2020-09-03T04:01:22.091266Z 0 [Note] Shutting down plugin 'INNODB_FT_INDEX_TABLE'
2020-09-03T04:01:22.091280Z 0 [Note] Shutting down plugin 'INNODB_FT_INDEX_CACHE'
2020-09-03T04:01:22.091294Z 0 [Note] Shutting down plugin 'INNODB_FT_CONFIG'
2020-09-03T04:01:22.091309Z 0 [Note] Shutting down plugin 'INNODB_FT_BEING_DELETED'
2020-09-03T04:01:22.091323Z 0 [Note] Shutting down plugin 'INNODB_FT_DELETED'
2020-09-03T04:01:22.091337Z 0 [Note] Shutting down plugin 'INNODB_FT_DEFAULT_STOPWORD'
2020-09-03T04:01:22.091351Z 0 [Note] Shutting down plugin 'INNODB_METRICS'
2020-09-03T04:01:22.091365Z 0 [Note] Shutting down plugin 'INNODB_TEMP_TABLE_INFO'
2020-09-03T04:01:22.091379Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_POOL_STATS'
2020-09-03T04:01:22.091393Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE_LRU'
2020-09-03T04:01:22.091413Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE'
2020-09-03T04:01:22.091432Z 0 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX_RESET'
2020-09-03T04:01:22.091450Z 0 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX'
2020-09-03T04:01:22.091464Z 0 [Note] Shutting down plugin 'INNODB_CMPMEM_RESET'
2020-09-03T04:01:22.091478Z 0 [Note] Shutting down plugin 'INNODB_CMPMEM'
2020-09-03T04:01:22.091503Z 0 [Note] Shutting down plugin 'INNODB_CMP_RESET'
2020-09-03T04:01:22.091517Z 0 [Note] Shutting down plugin 'INNODB_CMP'
2020-09-03T04:01:22.091531Z 0 [Note] Shutting down plugin 'INNODB_LOCK_WAITS'
2020-09-03T04:01:22.091545Z 0 [Note] Shutting down plugin 'INNODB_LOCKS'
2020-09-03T04:01:22.091559Z 0 [Note] Shutting down plugin 'INNODB_TRX'
2020-09-03T04:01:22.091573Z 0 [Note] Shutting down plugin 'InnoDB'
2020-09-03T04:01:22.091663Z 0 [Note] InnoDB: FTS optimize thread exiting.
2020-09-03T04:01:22.091825Z 0 [Note] InnoDB: Starting shutdown...
2020-09-03T04:01:22.192095Z 0 [Note] InnoDB: Dumping buffer pool(s) to /var/lib/mysql/ib_buffer_pool
2020-09-03T04:01:22.192660Z 0 [Note] InnoDB: Buffer pool(s) dump completed at 200903 4:01:22
2020-09-03T04:01:23.401986Z 0 [Note] InnoDB: Shutdown completed; log sequence number 2629951
2020-09-03T04:01:23.403994Z 0 [Note] InnoDB: Removed temporary tablespace data file: "ibtmp1"
2020-09-03T04:01:23.404040Z 0 [Note] Shutting down plugin 'MyISAM'
2020-09-03T04:01:23.404062Z 0 [Note] Shutting down plugin 'MRG_MYISAM'
2020-09-03T04:01:23.404079Z 0 [Note] Shutting down plugin 'PERFORMANCE_SCHEMA'
2020-09-03T04:01:23.404124Z 0 [Note] Shutting down plugin 'MEMORY'
2020-09-03T04:01:23.404140Z 0 [Note] Shutting down plugin 'sha256_password'
2020-09-03T04:01:23.404154Z 0 [Note] Shutting down plugin 'mysql_native_password'
2020-09-03T04:01:23.404304Z 0 [Note] Shutting down plugin 'binlog'
2020-09-03T04:01:23.404889Z 0 [Note] /usr/sbin/mysqld: Shutdown complete
2020-09-03T04:01:23.454874Z mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
2020-09-03T04:01:27.408250Z mysqld_safe Logging to '/var/log/mysql/error.log'.
2020-09-03T04:01:27.435494Z mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
2020-09-03T04:01:27.655695Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-09-03T04:01:27.657901Z 0 [Note] /usr/sbin/mysqld (mysqld 5.7.29-0ubuntu0.16.04.1) starting as process 2448 ...
2020-09-03T04:01:27.663256Z 0 [Note] InnoDB: PUNCH HOLE support available
2020-09-03T04:01:27.663337Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2020-09-03T04:01:27.663360Z 0 [Note] InnoDB: Uses event mutexes
2020-09-03T04:01:27.663381Z 0 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
2020-09-03T04:01:27.663406Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.8
2020-09-03T04:01:27.663427Z 0 [Note] InnoDB: Using Linux native AIO
2020-09-03T04:01:27.663819Z 0 [Note] InnoDB: Number of pools: 1
2020-09-03T04:01:27.664002Z 0 [Note] InnoDB: Using CPU crc32 instructions
2020-09-03T04:01:27.666579Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
2020-09-03T04:01:27.677778Z 0 [Note] InnoDB: Completed initialization of buffer pool
2020-09-03T04:01:27.680975Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
2020-09-03T04:01:27.693724Z 0 [Note] InnoDB: Highest supported file format is Barracuda.
2020-09-03T04:01:27.704600Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2020-09-03T04:01:27.704731Z 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2020-09-03T04:01:27.727414Z 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.
2020-09-03T04:01:27.728453Z 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active.
2020-09-03T04:01:27.728491Z 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active.
2020-09-03T04:01:27.729534Z 0 [Note] InnoDB: 5.7.29 started; log sequence number 2629951
2020-09-03T04:01:27.730084Z 0 [Note] InnoDB: Loading buffer pool(s) from /var/lib/mysql/ib_buffer_pool
2020-09-03T04:01:27.730274Z 0 [Note] Plugin 'FEDERATED' is disabled.
2020-09-03T04:01:27.732807Z 0 [Note] InnoDB: Buffer pool(s) load completed at 200903 4:01:27
2020-09-03T04:01:27.738382Z 0 [Note] Found ca.pem, server-cert.pem and server-key.pem in data directory. Trying to enable SSL support using them.
2020-09-03T04:01:27.738446Z 0 [Note] Skipping generation of SSL certificates as certificate files are present in data directory.
2020-09-03T04:01:27.739055Z 0 [Warning] CA certificate ca.pem is self signed.
2020-09-03T04:01:27.739102Z 0 [Note] Skipping generation of RSA key pair as key files are present in data directory.
2020-09-03T04:01:27.739186Z 0 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
2020-09-03T04:01:27.739209Z 0 [Note] - '0.0.0.0' resolves to '0.0.0.0';
2020-09-03T04:01:27.739246Z 0 [Note] Server socket created on IP: '0.0.0.0'.
2020-09-03T04:01:27.747127Z 0 [Note] Event Scheduler: Loaded 0 events
2020-09-03T04:01:27.747626Z 0 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.7.29-0ubuntu0.16.04.1' socket: '/var/run/mysqld/mysqld.sock' port: 3306 (Ubuntu)
2020-09-03T04:01:28.186506Z 2 [Note] Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)
2020-09-03T04:01:28.209393Z 3 [Note] Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)
2020-09-03T04:01:38.352035Z 4 [Note] Aborted connection 4 to db: 'mattermost' user: 'mmuser' host: 'localhost' (Got an error reading communication packets)
2020-09-03T04:01:55.776677Z 10 [Note] Aborted connection 10 to db: 'mattermost' user: 'mmuser' host: 'localhost' (Got an error reading communication packets)
Steps to reproduce
Just installed Mattermost via UCS App Center
Expected behavior
I want to login in and try mattermost 
but there seems something wrong with the internal sql db
Observed behavior
The mysqld is running inside the container and i can login with the credentials found inside config files (mmuser) the user ist working and is able to the see database mattermost but the login fails on server start