Experiencing sporadic connection issues

[marcusmoore]

Hi there!

I was wondering if anyone else experienced checks failing because of a connection issue?

We get sporadic errors that are variations of this:

mysql on xxxx
Failed to run: kex_exchange_identification: Connection closed by remote host
Connection closed by xxx.xxx.xxx.xxx port 22

ubuntu-version on xxxx
Failed to run: kex_exchange_identification: read: Connection reset by peer
Connection reset by xxx.xxx.xxx.xxx port 22

A few things we've noticed:

• It happens very sporadically. Sometimes it won't happen for a couple days and other times it will happen every couple hours and then be ok again
• It happens for both built-in checks like MySQL and Disk Space as well as checks that we've made (like ubuntu-version in the example above)
• It's only one client that will fail a check for this reason at a time and there isn't a pattern for which one it will be
• Usually the check goes green again after 3 minutes

About our environment:

• We're checking between 5-10 servers
• The clients being checked are on DigitalOcean and the monitor is on Linode

Troubleshooting:

• After seeing the comment here we set concurrent_ssh_connections to 1 and it didn't help
• We also thought the client servers were blocking the connection via a firewall but the logs, from what we can tell, don't show anything like that happening

I don't think the package is to blame here, it seems like it's doing what it is supposed to and the ssh connection between the servers is having sporadic issues.

I'm opening this up as a discussion here to see if this catches the eye of someone that has an idea of what is going on and can share their knowledge. It'll also be helpful for the people googling laravel-server-monitor and kex_exchange_identification and not seeing anyone else asking about it 😄