I have forgot why I upgraded my blog to PHP7 and MySQL5.7, but I just did it.
First have to say, even I had no upgrade plan for such thing. At that time I thought I could upgrade the MySQL rpm to 5.7, then started MySQL database and it should upgrade my database automatically. The worse thing was that I upgraded the PHP to version 7 at the same time, and some modules were not installed at the beginning.
After the upgrade, I rebooted the server and tried to access my website, while just got a blank page. From the log of Nginx, I found the socket file was changed after the php-fpm update, then I changed it accordingly. While still got blank page, and from the error log of php-fpm, I found the json extension of PHP was not installed, so I installed it and some other extensions, then restarted the php-fpm service, and got an error message that the database could not be connected.
From the log of mysql service, I got the error like the title of this blog. So after the upgrade, the mysqld could not be started. I searched and this one saved me:
MySQLd doesn't start after brew upgrade from 5.6 to 5.7
So the steps to fix this issue are easy:
- run as mysql user:
- ---one session---
- /usr/sbin/mysqld --skip-grant-tables
- ---another session---
- /usr/bin/mysql_upgrade
- killall mysqld
I post the log of command '/usr/bin/mysql_upgrade' as below:
- -bash-4.1$ /usr/bin/mysql_upgrade
- Checking if update is needed.
- Checking server version.
- Running queries to upgrade MySQL server.
- Checking system database.
- mysql.columns_priv OK
- mysql.db OK
- mysql.engine_cost OK
- mysql.event OK
- mysql.func OK
- mysql.general_log OK
- mysql.gtid_executed OK
- mysql.help_category OK
- mysql.help_keyword OK
- mysql.help_relation OK
- mysql.help_topic OK
- mysql.host OK
- mysql.innodb_index_stats OK
- mysql.innodb_table_stats OK
- mysql.ndb_binlog_index OK
- mysql.plugin OK
- mysql.proc OK
- mysql.procs_priv OK
- mysql.proxies_priv OK
- mysql.server_cost OK
- mysql.servers OK
- mysql.slave_master_info OK
- mysql.slave_relay_log_info OK
- mysql.slave_worker_info OK
- mysql.slow_log OK
- mysql.tables_priv OK
- mysql.time_zone OK
- mysql.time_zone_leap_second OK
- mysql.time_zone_name OK
- mysql.time_zone_transition OK
- mysql.time_zone_transition_type OK
- mysql.user OK
- Upgrading the sys schema.
- Checking databases.
- blog.wp_commentmeta OK
- blog.wp_comments
- error : Table upgrade required. Please do "REPAIR TABLE `wp_comments`" or dump/reload to fix it!
- blog.wp_links
- error : Table upgrade required. Please do "REPAIR TABLE `wp_links`" or dump/reload to fix it!
- blog.wp_options OK
- blog.wp_postmeta OK
- blog.wp_posts
- error : Table upgrade required. Please do "REPAIR TABLE `wp_posts`" or dump/reload to fix it!
- blog.wp_term_relationships OK
- blog.wp_term_taxonomy OK
- blog.wp_termmeta OK
- blog.wp_terms OK
- blog.wp_usermeta OK
- blog.wp_users
- error : Table upgrade required. Please do "REPAIR TABLE `wp_users`" or dump/reload to fix it!
- sys.sys_config OK
- wiki.archive OK
- wiki.category OK
- wiki.categorylinks
- error : Table rebuild required. Please do "ALTER TABLE `categorylinks` FORCE" or dump/reload to fix it!
- wiki.change_tag OK
- wiki.externallinks OK
- wiki.filearchive OK
- wiki.hitcounter OK
- wiki.image OK
- wiki.imagelinks OK
- wiki.interwiki OK
- wiki.ipblocks OK
- wiki.iwlinks OK
- wiki.job OK
- wiki.l10n_cache OK
- wiki.langlinks OK
- wiki.log_search OK
- wiki.logging OK
- wiki.module_deps OK
- wiki.msg_resource OK
- wiki.msg_resource_links OK
- wiki.objectcache
- error : Table rebuild required. Please do "ALTER TABLE `objectcache` FORCE" or dump/reload to fix it!
- wiki.oldimage OK
- wiki.page OK
- wiki.page_props OK
- wiki.page_restrictions OK
- wiki.pagelinks OK
- wiki.protected_titles OK
- wiki.querycache OK
- wiki.querycache_info OK
- wiki.querycachetwo OK
- wiki.recentchanges OK
- wiki.redirect OK
- wiki.revision OK
- wiki.searchindex OK
- wiki.site_identifiers OK
- wiki.site_stats OK
- wiki.sites OK
- wiki.tag_summary OK
- wiki.templatelinks OK
- wiki.text OK
- wiki.transcache OK
- wiki.updatelog OK
- wiki.uploadstash OK
- wiki.user OK
- wiki.user_former_groups OK
- wiki.user_groups OK
- wiki.user_newtalk OK
- wiki.user_properties OK
- wiki.valid_tag OK
- wiki.watchlist OK
- Repairing tables
- blog.wp_comments
- Note : TIME/TIMESTAMP/DATETIME columns of old format have been upgraded to the new format.
- status : OK
- blog.wp_links
- Note : TIME/TIMESTAMP/DATETIME columns of old format have been upgraded to the new format.
- status : OK
- blog.wp_posts
- Note : TIME/TIMESTAMP/DATETIME columns of old format have been upgraded to the new format.
- status : OK
- blog.wp_users
- Note : TIME/TIMESTAMP/DATETIME columns of old format have been upgraded to the new format.
- status : OK
- `wiki`.`categorylinks`
- Running : ALTER TABLE `wiki`.`categorylinks` FORCE
- status : OK
- `wiki`.`objectcache`
- Running : ALTER TABLE `wiki`.`objectcache` FORCE
- status : OK
- Upgrade process completed successfully.
- Checking if update is needed.
When I restarted mysql service, finally I could open my website again.
One more thing was about the W3TC plugin. When I wanted to change the cache service to others, I always got error message that it could not create directory under wp-content/cache folder. I confirmed the nginx user had read and write permissions of this folder but I still got the error. I could not find any error log about it, so at last I had to grant the 777 to the cache folder, then I found a tmp directory was created and the user name was php-fpm. So I knew I should grant write permission to php-fpm user, and this could be finished by 'setfacl -m u:php-fpm:rwx cache'.
Finally I got an error-free WordPress blog, but I needed to upgrade the wiki part. 
OK, let me have a rest, and upgrade it in another day.
