Reverse DNS lookup support

Rancher 1.x
1

Hi there,

Does Rancher internal DNS server configure reverse DNS entries for the names it holds?

My specific use case is configure a Rabbitmq cluster using autocluster plugin which look for a name and for each ip that name returns try to get the correspondent dns name.

A more general example is simply doing a couple of nslookups in an environment with at least a service with a minimum scale of 2 nodes:

root@a44d0dc0d4e8:/# nslookup bi
Server:         169.254.169.250
Address:        169.254.169.250#53

Name:   bi.bi-stg.rancher.internal
Address: 10.42.104.226
Name:   bi.bi-stg.rancher.internal
Address: 10.42.32.141

root@a44d0dc0d4e8:/# nslookup  10.42.104.226
Server:         169.254.169.250
Address:        169.254.169.250#53

** server can't find 226.104.42.10.in-addr.arpa: NXDOMAIN
1 Like
2

Hi,

For instance, it’s not the case. Reverse dns is not managed by rancher …

But !!! I’m also very interested in ! It would open ability to create very smooth catalog entries for hadoop like projects (with relies heavily on reverse DNS). It would be amazing if rancher internal DNS would have this kinda feature (including the ability to answer to host’s ip reverse !)

Let me know if there is any changes about that !

3

The actual rancher-dns service supports PTR, we just don’t configure any answers.

Reverse for managed network container IPs (10.42.x.y) should be easy enough (I just volunteer @alena :smile:). Other network modes and host IPs would not be supported, as they are not our IPs to manage and should have their own PTR records in upstream DNS.

1 Like
4

It would be amazing :slight_smile:

5

Just to be sure, the PTR implementation in rancher would be able to answer dock hostname when requesting on rancher managed ip address ? Am I wrong ?

6

Any update on this issue? This is a feature that would really come in handy when setting up Hadoop clusters.

7

+1 :slight_smile: Adding PTR records for every container using its stack-service-nodeId name would be great. I just stumbled about not being able to use rabbitmq’s new dns autodiscover-feature due to missing reverse DNS resolves. (Rancher Server v. 1.6.14) - Thanks a lot!

8

At least It would be awesome to be able to get the hostname of the leader or services at giddyup:

So I can run sth like:
giddyup service hostnames or giddyup service containers --hostname

or at least for the leader:
giddyup leader get hostname