ECONNRESET errors when idling

I’m trying to figure out the source of the error below, or how to catch it properly and mitigate it. I am using LDAPJS as part of an identity management pipeline to move user accounts from our ERP into Active Directory (connected over TLS with a self-signed cert). There is often idle periods in the database where no events are being dispatched, and in turn LDAPJS raises these exceptions when I assume it has nothing to do.

12:20:54 bsis-0 Error: read ECONNRESET
    at exports._errnoException (util.js:812:11)
    at TLSWrap.onread (net.js:542:26)
2015-11-03 12:20:54: App name:bsis id:0 exited with code 1
12:20:54 PM2 App name:bsis id:0 exited with code 1
2015-11-03 12:21:54: Starting execution sequence in -fork mode- for app name:bsis id:0
12:21:54 PM2 Starting execution sequence in -fork mode- for app name:bsis id:0
2015-11-03 12:21:54: App name:bsis id:0 online
12:21:54 PM2 App name:bsis id:0 online
12:21:54 bsis-0 WARNING: NODE_APP_INSTANCE value of '0' did not match any instance config file names.
12:21:54 bsis-0 WARNING: See https://github.com/lorenwest/node-config/wiki/Strict-Mode
12:37:54 bsis-0 Error: read ECONNRESET
    at exports._errnoException (util.js:812:11)
    at TLSWrap.onread (net.js:542:26)
2015-11-03 12:37:54: App name:bsis id:0 exited with code 1
12:37:54 PM2 App name:bsis id:0 exited with code 1
2015-11-03 12:38:54: Starting execution sequence in -fork mode- for app name:bsis id:0
12:38:54 PM2 Starting execution sequence in -fork mode- for app name:bsis id:0
2015-11-03 12:38:54: App name:bsis id:0 online
12:38:54 PM2 App name:bsis id:0 online
12:38:54 bsis-0 WARNING: NODE_APP_INSTANCE value of '0' did not match any instance config file names.
12:38:54 bsis-0 WARNING: See https://github.com/lorenwest/node-config/wiki/Strict-Mode
12:54:55 bsis-0 Error: read ECONNRESET
    at exports._errnoException (util.js:812:11)
    at TLSWrap.onread (net.js:542:26)
2015-11-03 12:54:55: App name:bsis id:0 exited with code 1
12:54:55 PM2 App name:bsis id:0 exited with code 1

They only show up because of my process.on('uncaughtException') handler which in turns logs the event and then auto-restarts the broker.

Ideas?

[randomsock]

👍

Thanks very much for doing the digging @tapmodo. reconnect: true does indeed auto-reconnect after this failure. This strikes me as a really important resilience feature so is a bit surprising it’s not documented. You do still need the client.on('error', ...) handler to stop the disconnection from bringing the process down first, as @pfmooney pointed out.

So an over-simplified solution looks like:

var options = {
    url: 'ldap://myad.foo.net:3268',
    reconnect: true
};
var client = ldapjs.createClient(options);
client.on('error', function(err) {
    console.warn('LDAP connection failed, but fear not, it will reconnect OK', err);
});

Job done - thanks guys!

[tapmodo]

As noted above, the documentation for the Client API doesn’t mention auto-reconnecting or how to handle an eventual ECONNRESET from the server. I can’t imagine an LDAP server that never closes or resets the connection, or never goes down. Appears to be option reconnect: true?

The documentation also does not mention how to close a connection, which is necessary if you are writing a small script that should gracefully shut down after doing its work. I looked in the source and appears this can be done with client.destroy()

Both of these points would be useful to mention in the documentation. Thanks!