Redis Failover, No Good Slave
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I tried this technique, telling the slave that I wanted it to be able to be a master. No luck there either. A Google Group had suggested this.
127.0.0.1:6379> slaveof no one OK -
No one wants to be a slave.
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@thecreativeone91 said:
No one wants to be a slave.
No,.. but if you have children you are one by default. Apologies for the drift there.
What about this:
slaveof 192.168.1.1 6379where you would put in your correct IP.
Do you need to authenticate the slave to the master?
Setting a slave to authenticate to a master
If your master has a password via requirepass, it's trivial to configure the slave to use that password in all sync operations.
To do it on a running instance, use redis-cli and type:config set masterauth <password>To set it permanently, add this to your config file:
masterauth <password>both from:
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The slave says that it is fully authenticated and synced.
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Tried to lower the quorum number to one, did nothing.
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Added a second Sentinel but the new Sentinel can see the original, but the original doesn't see it. Argh.
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Increased the slave timeout to 90 seconds. Still nothing.
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Mostly just putting this here for future reference. Still not making any progress.
https://gennadny.wordpress.com/2015/01/06/meet-redis-masters-slaves-and-scaling-out/
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For anyone as clueless as I
"Redis is an open source, BSD licensed, advanced key-value cache and store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets, sorted sets, bitmaps and hyperloglogs."
Clarified that right up didn't it
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@MattSpeller said:
For anyone as clueless as I
"Redis is an open source, BSD licensed, advanced key-value cache and store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets, sorted sets, bitmaps and hyperloglogs."
Clarified that right up didn't it
Or much simpler, it is one of the more popular NoSQL databases.
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Redis is also the default database for NodeBB. But Redis doesn't scale like MongoDB and is nowhere near as robust. So MangoLassi runs on MongoDB, not Redis. We are practically the only NodeBB site doing that, though. We are the biggest NodeBB traffic site, as far as I know.
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I should add that this is the command I am using to force a failover:
SENTINEL failover mymaster -
Some docs here but they don't really help...
http://objectrocket.com/blog/how-to/introduction-to-redis-sentinel
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In cool, ML news, on Duck Duck Go, this thread is the number one search hit for this error. Not very encouraging for finding an answer, but good that ML is getting that kind of SEO now!
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Other threads of people having the issue but no resolution.
http://grokbase.com/t/gg/redis-db/141x9xyjcw/sentinel-2-8-4-nogoodslave-in-manual-failover
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Here is what the error in the logs looks like...
[14804] 04 May 12:12:05.076 # +new-epoch 18 [14804] 04 May 12:12:05.076 # +try-failover master mymaster 127.0.0.1 6379 [14804] 04 May 12:12:05.078 # +vote-for-leader 78e27a9a509327e6c853535957c808cf8afd50cb 18 [14804] 04 May 12:12:05.078 # +elected-leader master mymaster 127.0.0.1 6379 [14804] 04 May 12:12:05.078 # +failover-state-select-slave master mymaster 127.0.0.1 6379 [14804] 04 May 12:12:05.140 # -failover-abort-no-good-slave master mymaster 127.0.0.1 6379 -
Which really just tells us that it is trying, we already know that it is failing. No additional info in the logs. Pretty useless.
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Redis doesn't appear to even have this log entry documented:
failover-abort-no-good-slave -
Working through some ideas here...
https://groups.google.com/forum/#!topic/redis-db/M6WPJ0LnaWI
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@thecreativeone91 said:
No one wants to be a slave.
I was going to say "it's so hard to find a good slave"
