Socket closed unexpectedly

[richardsun2021]

 this.redisClient = redis.createClient({
			url: `redis://${redisHost}:${redisPort}`,
			socket: {
				connectTimeout: 60000,
				keepAlive: 60000,
				reconnectStrategy: (attempts) => {
					logger.log(`Redis reconnecting attempt ${attempts}`);
					if (attempts == 1) {
						console.log(`${this.constructor.name} failed to connect to ${redisHost}:${redisPort}. Reconnecting...`);
					}
					return 500;
				},
			},
			password: ******
		});
		this.redisClient.on('error', err => logger.error(err, "Redis v4 client error"));
		this.redisClient.on('connect', () => logger.log('Redis v4 is connect'));
		this.redisClient.on('reconnecting', () => logger.log('Redis v4 is reconnecting'));
		this.redisClient.on('ready', () => logger.log('Redis v4 is ready'));
		this.redisClient.connect(); 

between my app service and redis service, there is an aws NLB-network load balancer.
I have four redis client created, and every 2 minutes will get this error:
"error: Socket closed unexpectedly"

Environment:

• Node.js Version: "16.16"
• Redis Server Version: "6.2"
• Node Redis Version: "4.3.1"
• Platform: aws Ecs

[abhi12299]

Same issue here.. running Azure Redis Cache with TLS results in random "Socket closed unexpectedly" errors every 5-10mins after starting my application (on AKS). This error also occurs when running the app locally on my machine (no proxies/load balancers).

[schmod]

Try setting connectTimeout: false

I think this library is mis-using Node's Socket.setTimeout() method, and is tearing the connection down after any idle period of 60 seconds or more.

[yaroslavputria]

Try setting connectTimeout: false

@schmod, do you mean connectTimeout: 0? - socket.connectTimeout is number.

[richardsun2021]

it works fine for me locally, pre-production test found this issue.

Same issue here.. running Azure Redis Cache with TLS results in random "Socket closed unexpectedly" errors every 5-10mins after starting my application (on AKS). This error also occurs when running the app locally on my machine (no proxies/load balancers).

[abhi12299]

Switched to ioredis for now.. this library is not suitable for production use until the issue is fixed.

[richardsun2021]

Switched to ioredis for now.. this library is not suitable for production use until the issue is fixed.

while 3.* is stable, but no bloom module, for me would like to switch to 3.* and implement bloom by other lib.

[shawnlknight]

I am also seeing this issue and will not upgrade to v4 until it is resolved. Any word on this?!?

[leibale]

Hi everyone, sorry for the dealy, I was on vacation..

I wasn't able to reproduce the error with "docker run redis/redis-stack-server", can you please help me reproduce the issue so I'll be able to fix it?

[schmod]

I'll reiterate my previous comment about connectTimeout – the current implementation calls:

if (this.#options.connectTimeout) {
   socket.setTimeout(this.#options.connectTimeout, () => socket.destroy(new ConnectionTimeoutError()));
}

However, socket.setTimeout isn't a connection timeout – it's a timeout for any activity on the socket. Let it sit idle for too long, and it'll self-destruct.

From the Node docs:

Sets the socket to timeout after timeout milliseconds of inactivity on the socket. By default net.Socket do not have a timeout.

When an idle timeout is triggered the socket will receive a 'timeout' event but the connection will not be severed. The user must manually call socket.end() or socket.destroy() to end the connection.

I'm not sure if this is the cause of the issues described in this thread, but it's almost certainly a bug.

[leibale]

@schmod the timeout is reset to 0 after the connect event, see this line

[abhi12299]

@schmod for some context, I tried to ping the redis server in my health check endpoint, so that there's no inactivity (the health check endpoint is called every 5s). But the connection still terminates after a few minutes (~5-10mins).
This only happened when I connected to Azure Redis Cache and not when connecting to local redis instance.

PS, I also talked to Microsoft support team for the same but there wasn't any issue with the connection options and setup.

[leibale]

see #1598

[abhi12299]

@leibale I had already tried the ping approach, but this still doesn't work.. I guess there's some issue with the library because I've migrated to ioredis and it works perfectly fine. No drops whatsoever.