Not able to telnet from one AWS instance to another (to resolve master_not_discovered_exception)

user_14976099 0
Viewed 652

I have 2 AWS EC2 instances which have the same security group: my security group

When I'm running curl -XGET 'http://localhost:9200/_cluster/state/master_node?pretty' from the nodes (works only on master), I get: master_not_discovered_exception

I tried to telnet with port 9200 from one machine to another, and it doesn't work, so I think this the root cause (I'm able to telnet from my local machine.

I followed this guideline

What else I should check?

Update:

telnet works tnx to suggested solution, however issue was still persist. I was able to fix it after following this answer

aws-security-group telnet amazon-web-services amazon-ec2
1 Answers

It would be a good idea to check the following: -Are both aws machines in the same VPC/Subnet? -If they are not, are there any ACLs configured in any of the VPCs that would prevent communication? Check VPCs and subnets. -If they are not, is routing configured between the machines? -Does the security group allow connections to TCP 9200 from any machine? or from a specific ip/range/subnet? if this is the case, make sure the machines ips are included.

-Do you have any firewall running on the machines that could prevent connectivity? ( If they are linux machines, check firewalld/iptables, and disable it shortly for a test. If they are windows machines, do the same test with windows firewall. If you do this test, make sure the machines are not reachable from external sources for the test duration.

user_135152860
Related