Even number of nodes with garbd

I want to run the common setup where I have 2 data centers and need to use garbd in a 3rd. I have everything setup and working in the DC’s now I am working with garbd. I want to run garbd in EC2 so I needed to map public addresses back to the internal addresses in the DC’s to the cluster nodes. When I start garb in EC2 to the public mapped addresses everything goes into a confused state. I tried garb locally to the DC’s with internal addresses and it works as expected. Questions:

  • Is there a way around the external/internal ip mapping that won’t confuse garbd/cluster
  • Is it possible to run more than one garb (one in each DC that would avoid having to use a 3rd DC like EC2)

Wasn’t able to find anything specific to my problem so I figured I’d ask the community. Thanks for any info.