support bringing up more masters in terraform and quickstart scripts

[peebs]

This is a requirement for the etcd-scaling test to be run against a terraform-quickstart created cluster.

cc @aaronlevy @yifan-gu

[yifan-gu]

@pbx0 Code looks fine, how can I test this?

[peebs]

@yifan-gu Create a file called terraform.tfvars with the following info:

access_key_id = "<YOUR_KEY_HERE>"
access_key = "<YOUR_KEY_HERE>"
instance_tags = "yifan_test_terraform"
ssh_key = "<name of your ssh key on amazon>"
additional_masters = 2

Then run terraform apply
Then run ./start_cluster.sh

Now you should have a cluster running with 3 masters and 1 worker (the default). Check out the variables files to see all the inputs to terraform. You override any of those defaults via the terraform.tfvars file.

Oh and what ever ssh key you specify from AWS should have its private material be available to you on your machine for the ./start_cluster.sh to work

[yifan-gu]

@pbx0 Thanks, let me try it.

[aaronlevy]

lgtm (but lets hold off merging until tests are green)

[aaronlevy]

Actually "additional masters" is a bit vague. Can we just use a specific number: "master_count" or some such?

[peebs]

We could be more symmetrical and use num_masters and num_workers it'd just take adding a little logic to terraform to figure out that one of the num_masters is actually the bootstrap node and is special. So I think we'd want to validate that this number is 1 or greater or something like that in terraform.

I labeled it as addtional_masters to imply it doesn't include the bootstrap node because it was easier to write that way.

[aaronlevy]

ah I see. Can we add a comment / todo to this effect? (assuming you can have comments in tf files)

[peebs]

I added this to the variable description in the variables.tf file.

added a minor comment

[aaronlevy]

lgtm

[peebs]

Renamed init-bootstrap.sh -> back to init-master.sh so that tests will pass. Leaving the rename of init-worker.sh to init-node.sh