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Duplicate IP on CS Engines

I’m completing a training exercise to install and configure a swarm.

I have 4 VM’s, Ubuntu 14.04. The first (Node A) is successfully configured for Docker Data Center (trial).

Node A: Server version 1.12.6-cs8, Swarm - Active, Is Mgr = true, 1 mgr, 1 node

On to my second VM (Node B) to be configure as a DTR.

  1. I installed CS Engine from the following package. docker-engine_1.12.6-0-ubuntu-trusty_amd64.deb
  2. Hello-World…everything is happy.
  3. Try to join the swarm,docker swarm join --token <bla, bla, bla> 172.17.0.1:2377 (fails)
  4. ifconfig, docker0 on node B is also 172.17.0.1

I understand Docker utilizes the 172.17.0.0/16,

  1. my question is how do you install subsequent CS Engines and prevent docker0 assignment of the first IP in the range.
  2. now that it has, is there a way to simply manually change Node B to 172.12.0.2

Thanks!

Hmm… I’m not 100% sure what you’re asking but it seems you’re confusing the bridge IP (--bip) and the external advertise address. docker0 bridge is used for host-local container networking. You would usually want to docker swarm init --advertise-addr with the IP which external worker nodes will join to (e.g., the node’s private subnet IP which might be the IP of eth1, etc.).

You can specify an interface to advertise on too like docker swarm init --advertise-addr eth1. Then join on another node to the address you have advertised.

Ok, that makes sense, but when in ddc I simply took the default to add a node and what it generates is the following.

What am I missing?

I just overroad the docker0 address generated in the join command with the E0 and the node successfully joined, but than found there was an error in the console. I suspect since the UCP node is advertising 172.17.0.1:2377. While the node appears to join it doesn’t do so successfully.

I would like to understand why DDC generates token the string with docker0.

There does not seem to be a way to change the advertised address since it’s the only manager at this point and there’s no way to promote the other nodes.

Start over?

Thanks

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