Xenforo Change from memcached to Redis = XF crashes!

My Xenforo install has been running flawlessly memcached, but I would like to switch it over to Redis. No real reason, just that I'm bored and like to experiment with new things...on a live forum lol

This is now my second time trying Redis with the same outcome.

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I follow the instructions here: https://community.centminmod.com/posts/18863/

And here: https://community.centminmod.com/posts/18769/

I can see the Redis cache populating when I browse my forum but every 3-5 minutes my XF will go down and report server 500 error. Then after a couple minutes it comes back up. This cycle repeats.

I can not figure out why this is happening and defer to the experts here. For now I have switched back to memcached as I cannot figure this out and it has happened both times I've followed the instructions for Redis and Xenforo

I'm using latest stable .08 CMM install

Redis Log:

Code:

5246:M 08 Feb 13:15:02.087 # Server started, Redis version 3.0.7
5246:M 08 Feb 13:15:02.509 * DB saved on disk
5246:M 08 Feb 13:15:02.512 * DB loaded from append only file: 0.425 seconds
5246:M 08 Feb 13:15:02.512 * The server is now ready to accept connections on port 6379
5246:M 08 Feb 13:16:03.043 * 10000 changes in 60 seconds. Saving...
5246:M 08 Feb 13:16:03.043 * Background saving started by pid 5563
5563:C 08 Feb 13:16:03.048 * DB saved on disk
5563:C 08 Feb 13:16:03.048 * RDB: 0 MB of memory used by copy-on-write
5246:M 08 Feb 13:16:03.143 * Background saving terminated with success

 

This steps I have done are as follows:

Install Xenforo Redis Cache add-on

Edit XF config.php to reflect:

Code:

$config['cache']['enabled'] = true;
$config['cache']['cacheSessions'] = true;
$config['cache']['frontend'] = 'Core';
$config['cache']['frontendOptions'] = array(
'caching' => true,
'cache_id_prefix' => 'xfxx_',
'automatic_serialization' => false,
'lifetime' => 0
);

$config['cache']['backend'] = 'Redis';

$config['cache']['backendOptions'] = array(
'server' => '127.0.0.1',
'port' => 6379,
'use_lua' => true,
);
require(XenForo_Application::getConfigDir().'/SV/RedisCache/Installer.php');

Configure Redis LRU

Code:

maxmemory 100mb
maxmemory-policy allkeys-lru
maxmemory-samples 10
appendonly yes

Restarted Redis Server

Flush Redis Cache

Install phpRedisAdmin

 

PHP - 5.6.17

Code:

[root@einstein ~]# php --ini
Configuration File (php.ini) Path: /usr/local/lib
Loaded Configuration File:         /usr/local/lib/php.ini
Scan for additional .ini files in: /etc/centminmod/php.d
Additional .ini files parsed:      /etc/centminmod/php.d/a_customphp.ini,
/etc/centminmod/php.d/curlcainfo.ini,
/etc/centminmod/php.d/geoip.ini,
/etc/centminmod/php.d/igbinary.ini,
/etc/centminmod/php.d/imagick.ini,
/etc/centminmod/php.d/memcache.ini,
/etc/centminmod/php.d/memcached.ini,
/etc/centminmod/php.d/mongodb.ini,
/etc/centminmod/php.d/redis.ini,
/etc/centminmod/php.d/zendopcache.ini,
/etc/centminmod/php.d/zzzz_phpsessions.ini

Is that what you are looking for?

 

I'm not sure why it's happening either. It's driving me nuts!

Good idea on disabling the modules I don't use.

 

Could Zend OpCache be causing problems with Redis LRU cache?

 

Yeah I posted the redis.log file contents in my first post. Doesn't look as though there is anything in there that is helpful to the situation

 

Not sure how to know if Redis goes down along with XF. I don't think it is as that would probably be reflected in the log file.

This is a Linode KVM with 1gb memory. Currently only using around 350mb of that 1gb

 

I did make that change to vm.overcommit_memory and then ran sysctl -p

I made sure to follow those directions perfectly. Maybe this evening I will switch back over to Redis and try to catch it crashing or something.

 

The only addon's I have are Digital Point Bettery Analytics and Pixel Exit's Admin Center.

I will post up the output shortly.

 

Forums are giving error 500 now every other minute, but Redis server is up the entire time. Cleared all browser cache as well, same issue. I feel like I"m not meant to run Redis lol

Code:

# Server
redis_version:3.0.7
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:5ece30e075eed8d2
redis_mode:standalone
os:Linux 4.1.5-x86_64-linode61 x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:4.4.7
process_id:20806
run_id:24fe9b81ddc49a531482ab0497b1fd771b4172c3
tcp_port:6379
uptime_in_seconds:604
uptime_in_days:0
hz:10
lru_clock:12120764
config_file:/etc/redis.conf

# Clients
connected_clients:1
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0

# Memory
used_memory:1153280
used_memory_human:1.10M
used_memory_rss:4313088
used_memory_peak:20280632
used_memory_peak_human:19.34M
used_memory_lua:52224
mem_fragmentation_ratio:3.74
mem_allocator:jemalloc-3.6.0

# Persistence
loading:0
rdb_changes_since_last_save:135
rdb_bgsave_in_progress:0
rdb_last_save_time:1454961232
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:0
rdb_current_bgsave_time_sec:-1
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_current_size:11736339
aof_base_size:11197186
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:233
total_commands_processed:6172
instantaneous_ops_per_sec:0
total_net_input_bytes:833408
total_net_output_bytes:37544967
instantaneous_input_kbps:0.00
instantaneous_output_kbps:0.00
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
evicted_keys:0
keyspace_hits:5262
keyspace_misses:264
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:429
migrate_cached_sockets:0

# Replication
role:master
connected_slaves:0
master_repl_offset:0
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0

# CPU
used_cpu_sys:0.53
used_cpu_user:0.72
used_cpu_sys_children:0.00
used_cpu_user_children:0.00

# Cluster
cluster_enabled:0

# Keyspace
db0:keys=68,expires=12,avg_ttl=45330798

 

I just changed the cache_id_prefix in XF config.php from the value that it was previously set at for memcached. We are going on 5 minutes or so and everything is solid. Interesting...

For some reason the header on the forum which is almost exactly the same as the one here on CMM loads very slow with Redis

 

Spoke too soon. XF just broke again with error 500. Redis server is still running.

Refreshed a few times and things are working again. what the heck is going on

 

Just found these errors in php-fpm

Code:

[08-Feb-2016 20:09:33 UTC] PHP Fatal error:  Zend_Cache::throwException(): Failed opening required 'Zend/Cache/Exception.php' (include_path='/home/nginx/domains/xxx$
[08-Feb-2016 20:09:33 UTC] PHP Warning:  Uncaught exception 'ErrorException' with message 'require_once(): open_basedir restriction in effect. File(/home/nginx/domains/xxx$
Stack trace:
#0 /home/nginx/domains/xxx/public/library/Zend/Cache.php(208): XenForo_Application::handlePhpError(2, 'require_once():...', '/home/nginx/dom...', 208, Array)
#1 /home/nginx/domains/xxx/public/library/Zend/Cache.php(208): Zend_Cache::throwException()
#2 /home/nginx/domains/xxx/public/library/Zend/Cache.php(148): Zend_Cache::throwException('file Zend/Cache...')
#3 /home/nginx/domains/xxx/public/library/Zend/Cache.php(94): Zend_Cache::_makeBackend('Redis', Array, false, false)
#4 /home/nginx/domains/xxx/public/library/XenForo/Application.php(762): Zend_Cache::factory('Core', 'Redis', Array in /home/nginx/domains/xxx/publ$
[08-Feb-2016 20:09:33 UTC] PHP Fatal error:  Zend_Cache::throwException(): Failed opening required 'Zend/Cache/Exception.php' (include_path='/home/nginx/domains/xxx$