Status: Not Connected despite plugin can see Redis server

  • Resolved CodeBard

    (@codebard)


    4 years, 10 months ago

    Kubernetes, using a custom docker image with debian buster PHP 7.3 fpm, Apache. Connecting to an in-cluster Redis cluster directly. No matter which version of php-redis i install (4.2.0 Debian Buster default, or, 5.2.2 latest or 5.1.0 version from PECL) i still get status Not Connected. The plugin can see the Redis server and ping it however, also can get its info. Using a sidecar im able to connect to the server and query it easily with redis-cli. The Redis cluster requires -c flag (allowing redirection of queries?) maybe that is the reason?

    Configuration is below:

    define( 'WP_REDIS_HOST', 'redis-cluster' );
define( 'WP_CACHE', true );
// define( 'WP_REDIS_CLIENT', 'pecl' );
define( 'WP_REDIS_PASSWORD', 'SOMEPASSWORD' );
define( 'WP_REDIS_DATABASE', '0' );
define( 'WP_CACHE_KEY_SALT', 'SOMESALTHERE' );
define( 'WP_REDIS_SELECTIVE_FLUSH', true );
define( 'WP_REDIS_DISABLE_BANNERS', true );

    Diagnostics in plugin:

    Status: Not Connected
Client: PhpRedis (v5.1.0)
Drop-in: Valid
Ping: 1
Redis Extension: 5.1.0
Predis Client: 1.1.1
PHP Version: 7.3.14-1~deb10u1
Redis Version: 5.0.9
Multisite: Yes
Global Prefix: ""
Blog Prefix: 1
WP_REDIS_HOST: "redis-cluster"
WP_REDIS_DATABASE: "0"
WP_CACHE_KEY_SALT: "SOMESALTHERE"
WP_REDIS_PASSWORD: "**********"
Global Groups: {
    "0": "blog-details",
    "1": "blog-id-cache",
    "2": "blog-lookup",
    "3": "global-posts",
    "4": "networks",
    "5": "rss",
    "6": "sites",
    "7": "site-details",
    "8": "site-lookup",
    "9": "site-options",
    "10": "site-transient",
    "11": "users",
    "12": "useremail",
    "13": "userlogins",
    "14": "usermeta",
    "15": "user_meta",
    "16": "userslugs",
    "33": "blog_meta"
}
Ignored Groups: [
    "counts",
    "plugins",
    "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",
    "blog_meta",
    "themes"
]
Unflushable Groups: []
Viewing 15 replies - 1 through 15 (of 18 total)
  • Plugin Author Till Krüss

    (@tillkruess)

    Hi @codebard. It’s unlikely Predis or PhpRedis, it sound like a permissions thing.

    Try placing file in your WP root and access it via HTTP, that might reveal the exception. 

    
<?php

$redis = new Redis;
$redis->connect('redis-cluster', 6379);

var_dump($redis);
    Thread Starter CodeBard

    (@codebard)

    thanks Till – with that file…

    object(Redis)#1 (0) { }

    …is the output.

    Plugin Author Till Krüss

    (@tillkruess)

    Try adding this line:

    
var_dump($redis->ping('test'));
    Thread Starter CodeBard

    (@codebard)

    The later bit of code prints out absolutely nothing. Not even an empty array.

    Plugin Author Till Krüss

    (@tillkruess)

    It must show at least null, if it doesn’t show anything, then there must be an error in your logs.

    Thread Starter CodeBard

    (@codebard)

    Im wondering if this has anything to do with Bitnami’s Redis cluster for Kubernetes.

    Plugin Author Till Krüss

    (@tillkruess)

    If redis-cli works then there must be some issue with PHP-FPM connecting to Redis. I’ve seen Kubernetes/Docker setups in the past and most of the time is’s a networking issues between “web” and “redis” containers.

    Thread Starter CodeBard

    (@codebard)

    The thing is that the plugin seems to be able to see the redis server and ping it, right? It returns 1. And when i was using another version of Redis client (phpredis) it was ponging to ‘ping’. So connectivity should be there? Or is there any other particular pitfall that mmay be aside from connectivity?

    Plugin Author Till Krüss

    (@tillkruess)

    Maybe this is a bug in the status display.

    Can you try flushing your Redis database, then load a WP page, then see how many keys are in Redis?

    Thread Starter CodeBard

    (@codebard)

    Below INFO stat outputs show the stats before and after db was flushed with FLUSHALL

    redis-cluster:6379> INFO stats
# Stats
total_connections_received:33500
total_commands_processed:150132
instantaneous_ops_per_sec:2
total_net_input_bytes:4729375
total_net_output_bytes:2340663
instantaneous_input_kbps:0.07
instantaneous_output_kbps:0.01
rejected_connections:0
sync_full:1
sync_partial_ok:0
sync_partial_err:1
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:238
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:1043
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0

redis-cluster:6379> INFO stats
# Stats
total_connections_received:33506
total_commands_processed:150159
instantaneous_ops_per_sec:1
total_net_input_bytes:4730216
total_net_output_bytes:2341410
instantaneous_input_kbps:0.05
instantaneous_output_kbps:0.01
rejected_connections:0
sync_full:1
sync_partial_ok:0
sync_partial_err:1
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:238
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:1043
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0

    Currently DBSIZE outputs 0.

    Thread Starter CodeBard

    (@codebard)

    I refreshed the site’s pages and visited some other urls in order to effect a cache read/write after flushing the db.

    Plugin Author Till Krüss

    (@tillkruess)

    Are you using a real cluster? If so you’ll need to use a different constant and not WP_REDIS_HOST.

    Can you post the full INFO command?

    Thread Starter CodeBard

    (@codebard)

    redis-cluster:6379> INFO
# Server
redis_version:5.0.9
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:19c09cb14abb2b16
redis_mode:cluster
os:Linux 4.19.0-0.bpo.6-amd64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:8.3.0
process_id:1
run_id:fac89c6f3024d0b95953da813edead2fe2a3e1d7
tcp_port:6379
uptime_in_seconds:84263
uptime_in_days:0
hz:10
configured_hz:10
lru_clock:12175140
executable:/opt/bitnami/redis/bin/redis-server
config_file:

# Clients
connected_clients:1
client_recent_max_input_buffer:2
client_recent_max_output_buffer:0
blocked_clients:0

# Memory
used_memory:2658648
used_memory_human:2.54M
used_memory_rss:12488704
used_memory_rss_human:11.91M
used_memory_peak:3465568
used_memory_peak_human:3.31M
used_memory_peak_perc:76.72%
used_memory_overhead:2578594
used_memory_startup:1463320
used_memory_dataset:80054
used_memory_dataset_perc:6.70%
allocator_allocated:3114320
allocator_active:3411968
allocator_resident:10473472
total_system_memory:8366104576
total_system_memory_human:7.79G
used_memory_lua:37888
used_memory_lua_human:37.00K
used_memory_scripts:0
used_memory_scripts_human:0B
number_of_cached_scripts:0
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
allocator_frag_ratio:1.10
allocator_frag_bytes:297648
allocator_rss_ratio:3.07
allocator_rss_bytes:7061504
rss_overhead_ratio:1.19
rss_overhead_bytes:2015232
mem_fragmentation_ratio:4.77
mem_fragmentation_bytes:9872056
mem_not_counted_for_evict:82
mem_replication_backlog:1048576
mem_clients_slaves:16922
mem_clients_normal:49694
mem_aof_buffer:82
mem_allocator:jemalloc-5.1.0
active_defrag_running:0
lazyfree_pending_objects:0

# Persistence
loading:0
rdb_changes_since_last_save:2
rdb_bgsave_in_progress:0
rdb_last_save_time:1589149208
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:0
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:4530176
aof_enabled:1
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:-1
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:0
aof_current_size:195
aof_base_size:154
aof_pending_rewrite:0
aof_buffer_length:0
aof_rewrite_buffer_length:0
aof_pending_bio_fsync:0
aof_delayed_fsync:0

# Stats
total_connections_received:34227
total_commands_processed:153402
instantaneous_ops_per_sec:1
total_net_input_bytes:4832952
total_net_output_bytes:2379022
instantaneous_input_kbps:0.04
instantaneous_output_kbps:0.00
rejected_connections:0
sync_full:1
sync_partial_ok:0
sync_partial_err:1
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:238
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:1043
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0

# Replication
role:master
connected_slaves:1
slave0:ip=10.244.11.19,port=6379,state=online,offset=117585,lag=0
master_replid:25b1900f429338f116f3534e9152bc5912037aba
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:117585
second_repl_offset:-1
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:1
repl_backlog_histlen:117585

# CPU
used_cpu_sys:70.030822
used_cpu_user:59.647139
used_cpu_sys_children:0.079644
used_cpu_user_children:0.143280

# Cluster
cluster_enabled:1

# Keyspace
    Plugin Author Till Krüss

    (@tillkruess)

    Yeah, you’ll have to use the cluster constants. You can read more about that in the readme.

    Thread Starter CodeBard

    (@codebard)

    Using

    define( 'WP_REDIS_CLUSTER', [
    'tcp://redis-cluster:6379?database=0&alias=node-01',
] );

    Instead of…

    define( 'WP_REDIS_HOST', 'redis-cluster' );

    I get…

    Connection Exception: Couldn't map cluster keyspace using any provided seed (RedisClusterException)

Viewing 15 replies - 1 through 15 (of 18 total)
  • The topic ‘Status: Not Connected despite plugin can see Redis server’ is closed to new replies.