Can you post your diagnostics?
Did you install Redis Server on your Droplet?
I did yes:
> service redis status
● redis-server.service - Advanced key-value store
Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2020-11-02 12:06:10 PST; 4 days ago
Docs: http://redis.io/documentation,
man:redis-server(1)
Main PID: 947 (redis-server)
Tasks: 4 (limit: 4620)
Memory: 144.4M
CGroup: /system.slice/redis-server.service
└─947 /usr/bin/redis-server 127.0.0.1:6379
Nov 02 12:06:09 droplet-openlitespeed-server systemd[1]: Starting Advanced key-value store...
Nov 02 12:06:10 droplet-openlitespeed-server systemd[1]: redis-server.service: Can't open PID file /run/redis/redis-server.pid (yet?) after start: Operation not permitted
Nov 02 12:06:10 droplet-openlitespeed-server systemd[1]: Started Advanced key-value store.
Here are the diagnostics:
Status: Connected
Client: PhpRedis (v5.2.2)
Drop-in: Valid
Disabled: No
Filesystem: Working
Ping: 1
Errors: []
PhpRedis: 5.2.2
Predis: Not loaded
Credis: Not loaded
PHP Version: 7.4.12
Plugin Version: 2.0.15
Redis Version: 5.0.7
Multisite: No
Global Prefix: "wp_"
Blog Prefix: "wp_"
WP_REDIS_PREFIX: "wednesdaynighthop.com"
WP_CACHE_KEY_SALT: "wednesdaynighthop.com"
Global Groups: [
"blog-details",
"blog-id-cache",
"blog-lookup",
"global-posts",
"networks",
"rss",
"sites",
"site-details",
"site-lookup",
"site-options",
"site-transient",
"users",
"useremail",
"userlogins",
"usermeta",
"user_meta",
"userslugs",
"redis-cache",
"blog_meta"
]
Ignored Groups: [
"counts",
"plugins",
"themes",
"wpfront-user-role-editor",
"tribe-events-non-persistent"
]
Unflushable Groups: []
Drop-ins: [
"advanced-cache.php v by ",
"Redis Object Cache Drop-In v2.0.15 by Till Krüss"
]
That looks like a one off error then, since it says “Connected”.
But I am getting a lot of them:
[06-Nov-2020 20:04:46 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 20:31:57 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:03:36 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:03:36 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:03:36 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:03:39 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:03:52 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:06:05 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:06:05 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:881
[06-Nov-2020 21:06:05 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:11:42 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:11:52 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:19:21 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:19:59 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:20:31 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
[06-Nov-2020 21:21:07 UTC] RedisException: read error on connection to 127.0.0.1:6379 in .../public_html/wp-content/object-cache.php:1357
I can’t assist with this, it’s specific to your server.
I’d recommend asking on Stack Overflow or the Digital Ocean community.
Thanks Till. I understand.
Just one question:
Could it be due to my settings appendonly to yes (for a separate nodeJS app) in redis.conf?
I see this in the redis-server.log file:
502894:M 06 Nov 2020 15:02:35.073 * Asynchronous AOF fsync is taking too long (disk is busy?). Writing the AOF buffer without waiting for fsync to complete, this may slow down Redis.
I will understand if you feel you cannot respond conclusively.
That could cause it yeah 👍🏻
Thanks!
Apparently I have two appendonly.aof files :/
/var/lib/redis/appendonly.aof
/data/appendonly.aof
That cannot be good, will fix.
The errors seem to be now gone, and it was entirely my bad. I had a regular redis server running with the server config and a separate redis server running through Docker with a different config (especially different appendonly.aof file locations). Most likely there were stomping on each other. I switched the Docker redis server to a different port and removed the appendonly setting from the regular server config.
Thank you for taking the time to answer my questions 🙂
Glad to hear it is resolved!
Looks like I claim victory too soon:
[08-Nov-2020 02:05:29 UTC] RedisException: read error on connection to /var/run/redis/redis-server.sock:0 in .../public_html/wp-content/object-cache.php:1357
Stack trace:
#0 .../public_html/wp-content/object-cache.php(1357): Redis->get('wednesdaynighth...')
#1 .../public_html/wp-content/object-cache.php(114): WP_Object_Cache->get('sm_session_db_v...', 'options', false, NULL)
#2 .../public_html/wp-includes/option.php(121): wp_cache_get('sm_session_db_v...', 'options')
#3 .../public_html/wp-content/plugins/wp-session-manager/includes/DatabaseHandler.php(37): get_option('sm_session_db_v...', '0.0')
#4 .../public_html/wp-content/plugins/wp-session-manager/wp-session-manager.php(96): EAMann\WPSession\DatabaseHandler::createTable()
#5 .../public_html/wp-includes/class-wp-hook.php(285): wp_session_manager_initialize()
#6 .../public_html/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#7 .../public_html/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#8 .../public_html/wp-settings.php(409): do_action('plugins_loaded')
#9 .../public_html/wp-config.php(124): require_once('/home/wednesday...')
#10 .../public_html/wp-load.php(37): require_once('/home/wednesday...')
#11 .../public_html/wp-blog-header.php(13): require_once('/home/wednesday...')
#12 .../public_html/index.php(17): require('/home/wednesday...')
#13 {main}
Will try to figure it out and post my findings.