Cannot connect to services running on LAN machines, from the same LAN

RouterOS General
1

I have situation that is odd, to me.

I am running some compute services on two machines on the LAN. 4 instances of the compute service run on each of the two machines. They use ports 3000-3003

The services appear to run correctly as I can telnet to them from the host machine (itself), but I am unable to telnet to a service running on a different machine. They also cannot be discovered on the network when I use the management software to connect to the compute services. Host machines are not blocking ports.

In other words I have this:

Compute machine 1: 192.168.88.xx: 3000-3003
Compute machine 2: 192.168.88.xy: 3000-3003
Management node: 192.168.88.xz

I can telnet to a service from machine 1 to machine 1, but I cannot telnet from machine 1 to machine 2 (and vice versa) and management node does not find any services on the LAN.

How do I enable LAN connectivity on the ports 3000-3003? Also I may need to run more services and more compute machines so a permanent solution that does not require messing with the firewall every time the compute topology changes would be preferable. I only need them to be accessible inside the same LAN.

Thank you,

V.

2

It is more likely this is a host firewall issue - on the same broadcast domain never really hits filter rules unless you have firewall filtering on the bridge interface enabled - within the same LAN it should all keep going. I don’t believe this to be a mikrotik problem at all, check firewall on the servers.

3

You were right… there was an obscure firewall in place on host compute machines that was set to close most ports for unknown services. All is well now