Auto reconnect doesn't work under certains circumstances

Hello,

When ready check is on and an MaxRetriesPerRequestError happens, a recoverFromFatalError is called in the ready check causing disconnect(true) to be called and will lead to abort to reconnection process.

This is leading us in a situation where express session associated to redisStore isn’t working anymore.

a quick and dirty fix for us is to disable ready check or set MaxRetriesPerRequest to -1

Our case to test the bug:

ioredis express client connected as a standalone redis configuration to redis-ha chart with haproxy enabled and 3 redis/sentinel behind. (haproxy is routing all requests to the master node) kill or scale to 0 haproxy. ioredis is entering the autoreconnect loop (with retrystrategy)

Adding this stack to help :

programname programname 2019-11-20T08:58:29.197Z ioredis:redis status[10.19.246.167:6379 (clientname)]: close -> reconnecting
programname programname 2019-11-20T08:58:29.197Z ioredis:connection reach maxRetriesPerRequest limitation, flushing command queue... v1
programname programname 2019-11-20T08:58:29.197Z ioredis:connection reach maxRetriesPerRequest limitation, flushing command queue... DONE v1
programname programname 2019-11-20T08:58:29.197Z ioredis:redis recoverFromFatalError MaxRetriesPerRequestError: Reached the max retries per request limit (which is 1). Refer to "maxRetriesPerRequest" option for details.
programname programname 2019-11-20T08:58:29.198Z ioredis:redis DISCONNECT CALLED v2 true
programname programname Trace
programname programname     at Redis.disconnect (/snapshot/programname/node_modules/ioredis/built/redis/index.js:323:10)
programname programname     at Redis.recoverFromFatalError (/snapshot/programname/node_modules/ioredis/built/redis/index.js:365:10)
programname programname     at /snapshot/programname/node_modules/ioredis/built/redis/event_handler.js:53:30
programname programname     at /snapshot/programname/node_modules/ioredis/built/redis/index.js:436:20
programname programname     at tryCatcher (/snapshot/programname/node_modules/standard-as-callback/built/utils.js:11:23)
programname programname     at promise.then (/snapshot/programname/node_modules/standard-as-callback/built/index.js:30:51)
programname programname     at process._tickCallback (internal/process/next_tick.js:68:7)

[shizhx]

reproduced method:

1. redis-server not started
2. new Redis() and call any command, e.g. get
3. ioredis will connect failed and retry(enable DEBUG and print retryAttempts)
4. once retryAttempts reach 20, start netcat nc -l 6379 as a fake redis-server
5. wait for a whlie, once ioredis connected to netcat and info command written, stop netcat
6. ioredis will reconnect and the reconnectTimeout task would always canceled by recoverFromFatalError
7. ioredis dead and get command will never return

[tupizz]

The error still here, even with the version 4.17.3…