REDIS Error “Service Unavailable” after upgrade to 2.4.2

  • Resolved nicole0155

    (@nicole0155)


    1 year, 8 months ago

    Dear Support Team,

    We have made the last upgrade to 2.4.2 and we have lost access to the website.

    After a reinstall the issue remains and we only can put the website working with a server restart and without the REDIS OBJECT CACHE plugin.

    The pages shows the following message “Service Unavailable The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.”

    At the server side, the redis service (redis_version:7.0.11) it’s working fine as usual and there were no changes at server or WordPress (where we have):


    define( ‘WP_REDIS_PREFIX’, ‘my-moms-site’ );
    define( ‘WP_REDIS_DATABASE’, 0 ); // 0-15
    define( ‘WP_REDIS_TIMEOUT’, 1 );
    define( ‘WP_REDIS_READ_TIMEOUT’, 1 );
    define( ‘WP_REDIS_PATH’, ‘/var/run/redis/redis.sock’ );
    define( ‘WP_REDIS_SCHEME’, ‘unix’ );

    Can you help?

    Thanks

    Nicole

    The page I need help with: [log in to see the link]

Viewing 13 replies - 1 through 13 (of 13 total)
  • Plugin Author Till Krüss

    (@tillkruess)

    Thanks for the report. We didn’t change anything in regards to connections in 2.4.2.

    I’d suggest to remove the wp-content/object-cache.php file and then go to Settings > Redis to see what exact error the plugin is showing.

    Just a hunch, what PHP Version Are you running?

    Thread Starter nicole0155

    (@nicole0155)

    I’m using php version 8.2.6. In the meantime I have added to additional lines at wp-config that I never used before:

    define( ‘WP_REDIS_HOST’, ‘127.0.0.1’ );
    define( ‘WP_REDIS_PORT’, 6379 );

    Now the systems is working with REDIS and without the plugin. Is there any advantage of using the plugin?

    Thanks.

    Thread Starter nicole0155

    (@nicole0155)

    Dear @tillkruess

    We couldn’t not acccess to Settings > Redis, since all the admin system became unavailable.

    However, since REDIS it’s working with WordPress (without the plugin) we have made again the plugin installation and it started to work.

    The only change was the 2 additional lines. Anyway we will continue with the plugin and the issue seems solved.

    Thanks.

    Plugin Author Till Krüss

    (@tillkruess)

    After deleting wp-content/object-cache.php you are still not able to access Settings > Redis?

    Plugin Author Till Krüss

    (@tillkruess)

    We’ve tagged a new version.

    Can you try deleting your wp-content/object-cache.php and starting over?

    Thread Starter nicole0155

    (@nicole0155)

    I have tried to temporary disable the REDIS at the plugin, and the error appeared again.

    Even if I delete the file wp-content/object-cache.php I do not have access to admin panel, so its not possible to check.

    Plugin Author Till Krüss

    (@tillkruess)

    Can you try deleting the wp-contents/plugins/redis-cache directory as well?

    Are you seeing any errors in your PHP error logs?

    Thread Starter nicole0155

    (@nicole0155)

    Yes, I have deleted wp-contents/plugins/redis-cache but can not have admin access. Also I have renamed all plugins directory, also without any inpact. Only after a full server restart I’m getting normal access.

    I did not found any related error on the php logs.

    After the server restart I can see the following in the redis plugin:

    Status: Not enabled
Client: 
Drop-in: Not installed
Disabled: No
PhpRedis: 5.3.7
Relay: Not loaded
Predis: 2.1.2
Credis: Not loaded
PHP Version: 8.2.6
Plugin Version: 2.4.3
Redis Version: Unknown
Multisite: No
Metrics: Disabled
Metrics recorded: 0
Filesystem: Working
WP_REDIS_SCHEME: "unix"
WP_REDIS_PATH: "/var/run/redis/redis.sock"
WP_REDIS_HOST: "127.0.0.1"
WP_REDIS_PORT: 6379
WP_REDIS_DATABASE: 0
WP_REDIS_TIMEOUT: 1
WP_REDIS_READ_TIMEOUT: 1
WP_REDIS_PREFIX: "my-moms-site"
WP_REDIS_PLUGIN_PATH: "(...)wp-content/plugins/redis-cache"
Drop-ins: [
    "advanced-cache.php v by ",
    "maintenance.php v by "
]

    However, after clicking “enable” I have lost again website access.

    Plugin Author Till Krüss

    (@tillkruess)

    You currently have WP_REDIS_HOST and WP_REDIS_PATH defined, you only need to use one.

    Are you able to connect to Redis server using redis-cli and if so are you connecting to 127.0.0.1 or /var/run/redis/redis.sock?

    Thread Starter nicole0155

    (@nicole0155)

    The connection is being done through the /var/run/redis/redis.sock. I manage to open the plugin with the redis running. However if I click a “flush cache” or “disable” button all the website stops working and no error logs exist.

    Here is the plugin data

    Status: Connected
Client: PhpRedis (v5.3.7)
Drop-in: Valid
Disabled: No
Ping: 1
Errors: []
PhpRedis: 5.3.7
Relay: Not loaded
Predis: 2.1.2
Credis: Not loaded
PHP Version: 8.2.6
Plugin Version: 2.4.3
Redis Version: 7.0.11
Multisite: No
Metrics: Enabled
Metrics recorded: 77
Filesystem: Working
Global Prefix: "c_"
Blog Prefix: "c_"
WP_REDIS_SCHEME: "unix"
WP_REDIS_PATH: "/var/run/redis/redis.sock"
WP_REDIS_PORT: 6379
WP_REDIS_DATABASE: 0
WP_REDIS_TIMEOUT: 1
WP_REDIS_READ_TIMEOUT: 1
WP_REDIS_PREFIX: "my-moms-site"
WP_REDIS_PLUGIN_PATH: ".../wp-content/plugins/redis-cache"
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",
    "code_snippets"
]
Ignored Groups: [
    "counts",
    "plugins",
    "themes",
    "theme_json"
]
Unflushable Groups: []
Groups Types: {
    "blog-details": "global",
    "blog-id-cache": "global",
    "blog-lookup": "global",
    "global-posts": "global",
    "networks": "global",
    "rss": "global",
    "sites": "global",
    "site-details": "global",
    "site-lookup": "global",
    "site-options": "global",
    "site-transient": "global",
    "users": "global",
    "useremail": "global",
    "userlogins": "global",
    "usermeta": "global",
    "user_meta": "global",
    "userslugs": "global",
    "redis-cache": "global",
    "counts": "ignored",
    "plugins": "ignored",
    "themes": "ignored",
    "blog_meta": "global",
    "theme_json": "ignored",
    "code_snippets": "global"
}
Drop-ins: [
    "advanced-cache.php v by ",
    "maintenance.php v by ",
    "Redis Object Cache Drop-In v2.4.3 by Till Krüss"

    Please have a look.

    Plugin Author Till Krüss

    (@tillkruess)

    In that case I need to see your PHP error logs, something is crashing hard and it won’t do it without reporting it.

    You can also enable debugging in WordPress to make it more verbose: https://www.ads-software.com/documentation/article/debugging-in-wordpress/

    Not sure about the relation, but I get the same results if I try to enable this plugin when JIT (opcache.jit) is enabled on PHP (won’t happen if opcache only is enabled, without enabling JIT).

    I’m using PHP-FPM 8.0 (there’s another application on the same virtual host that runs only on PHP 8.0), Apache 2.4, Ubuntu 22.04.

    APACHE LOG:

    [proxy_fcgi:error] [pid 23594:tid 139919474284096] [client 192.168.x.x:18631] AH01067: Failed to read FastCGI header, referer: https://mydomain.com/wp-admin/options-general.php?page=redis-cache
[proxy_fcgi:error] [pid 23594:tid 139919474284096] (104)Connection reset by peer: [client 192.168.x.x:18631] AH01075: Error dispatching request to : , referer: https://mydomain.com/wp-admin/options-general.php?page=redis-cache

    PHP LOG:

    WARNING: [pool mydomain.com] child 23544 exited on signal 11 (SIGSEGV - core dumped) after 18.812093 seconds from start
NOTICE: [pool mydomain.com] child 23813 started

    Redis Object Cache Diagnostics (before Enable Object Cache):

    Status: Not enabled
Client: 
Drop-in: Not installed
Disabled: No
PhpRedis: 5.3.7
Relay: Not loaded
Predis: 2.1.2
Credis: Not loaded
PHP Version: 8.0.29
Plugin Version: 2.4.3
Redis Version: Unknown
Multisite: No
Metrics: Disabled
Metrics recorded: 0
Filesystem: Working
WP_REDIS_PLUGIN_PATH: "/var/www/mydomain/wp-content/plugins/redis-cache"
WP_REDIS_PASSWORD: ********
Drop-ins: []

    Then, if I click the button “Enable Object Cache” of the plugin (with PHP’s opcache.jit enabled) the server goes 503 (Service Unavailable).

    Then, if I configure on php.ini opcache.jit=disable, then when I click the button “Enable Object Cache” of the plugin, it works, and shows this Diagnostics:

    Status: Connected
Client: PhpRedis (v5.3.7)
Drop-in: Valid
Disabled: No
Ping: 1
Errors: []
PhpRedis: 5.3.7
Relay: Not loaded
Predis: 2.1.2
Credis: Not loaded
PHP Version: 8.0.29
Plugin Version: 2.4.3
Redis Version: 7.0.12
Multisite: No
Metrics: Enabled
Metrics recorded: 17
Filesystem: Working
Global Prefix: "xxxxxx_"
Blog Prefix: "xxxxxx_"
WP_REDIS_PLUGIN_PATH: "/var/www/mydomain/wp-content/plugins/redis-cache"
WP_REDIS_PASSWORD: ******** 
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",
    "theme_json"
]
Unflushable Groups: []
Groups Types: {
    "blog-details": "global",
    "blog-id-cache": "global",
    "blog-lookup": "global",
    "global-posts": "global",
    "networks": "global",
    "rss": "global",
    "sites": "global",
    "site-details": "global",
    "site-lookup": "global",
    "site-options": "global",
    "site-transient": "global",
    "users": "global",
    "useremail": "global",
    "userlogins": "global",
    "usermeta": "global",
    "user_meta": "global",
    "userslugs": "global",
    "redis-cache": "global",
    "counts": "ignored",
    "plugins": "ignored",
    "themes": "ignored",
    "blog_meta": "global",
    "theme_json": "ignored"
}
Drop-ins: [
    "Query Monitor Database Class (Drop-in) v3.13.1 by John Blackbourn",
    "Redis Object Cache Drop-In v2.4.3 by Till Krüss"
]

    Thread Starter nicole0155

    (@nicole0155)

    Hi @cintyatakahaschi

    Thank for your comment. We have opcache JIT enabled.

    @tillkruess

    At the moment we don’t want to do more tests due to the stability of the site, so we are only working with REDIS using the command line.

    We will wait further news.

Viewing 13 replies - 1 through 13 (of 13 total)
  • The topic ‘REDIS Error “Service Unavailable” after upgrade to 2.4.2’ is closed to new replies.