Terraform: aws_route_table showing a change

Created on 30 Jun 2016 · 3Comments · Source: hashicorp/terraform

Terraform Version

Terraform v0.6.16

Affected Resource(s)

aws_route_table

Terraform Configuration Files

https://gist.github.com/rjinski/b61b37ed371c76b3965db22c6a425957

Debug Output

Refreshing Terraform state prior to plan...

...

The Terraform execution plan has been generated and is shown below.
Resources are shown in alphabetical order for quick scanning. Green resources
will be created (or destroyed and then created if an existing resource
exists), yellow resources are being changed in-place, and red resources
will be destroyed.

Note: You didn't specify an "-out" parameter to save this plan, so when
"apply" is called, Terraform can't guarantee this is what will execute.

~ aws_route_table.private.0
route.1031202073.cidr_block: "0.0.0.0/0" => ""
route.1031202073.gateway_id: "" => ""
route.1031202073.instance_id: "" => ""
route.1031202073.nat_gateway_id: "nat-06bd9ef37d96ac470" => ""
route.1031202073.network_interface_id: "" => ""
route.1031202073.vpc_peering_connection_id: "" => ""
route.2863962898.cidr_block: "" => "0.0.0.0/0"
route.2863962898.gateway_id: "" => "nat-06bd9ef37d96ac470"
route.2863962898.instance_id: "" => ""
route.2863962898.nat_gateway_id: "" => ""
route.2863962898.network_interface_id: "" => ""
route.2863962898.vpc_peering_connection_id: "" => ""

~ aws_route_table.private.1
route.2414893198.cidr_block: "" => "0.0.0.0/0"
route.2414893198.gateway_id: "" => "nat-068a007cc4ff8d721"
route.2414893198.instance_id: "" => ""
route.2414893198.nat_gateway_id: "" => ""
route.2414893198.network_interface_id: "" => ""
route.2414893198.vpc_peering_connection_id: "" => ""
route.2551236003.cidr_block: "0.0.0.0/0" => ""
route.2551236003.gateway_id: "" => ""
route.2551236003.instance_id: "" => ""
route.2551236003.nat_gateway_id: "nat-068a007cc4ff8d721" => ""
route.2551236003.network_interface_id: "" => ""
route.2551236003.vpc_peering_connection_id: "" => ""

Plan: 0 to add, 2 to change, 0 to destroy.

Expected Behavior

No changes

Actual Behavior

changes

Steps to Reproduce

No changes to configuration but rerunning terraform apply shows changes to the routing tables

bug provideaws

Source

rjinski

Most helpful comment

Hello –

Thank you for the gist of your config! I was able to reproduce your issue, and the key point is here:

~ aws_route_table.private.0
route.1031202073.gateway_id: "" => ""
route.1031202073.nat_gateway_id: "nat-06bd9ef37d96ac470" => ""
route.2863962898.gateway_id: "" => "nat-06bd9ef37d96ac470"
route.2863962898.nat_gateway_id: "" => ""

In your configuration, you're providing a NAT Gateway ID to the gateway_id attribute. Changing your config to use this:

  route {
    cidr_block     = "0.0.0.0/0"
    nat_gateway_id = "${element(aws_nat_gateway.nat.*.id, count.index)}"
  }

will resolve the issue here.

catsby on 30 Jun 2016

👍2

All 3 comments

Hello –

Thank you for the gist of your config! I was able to reproduce your issue, and the key point is here:

~ aws_route_table.private.0
route.1031202073.gateway_id: "" => ""
route.1031202073.nat_gateway_id: "nat-06bd9ef37d96ac470" => ""
route.2863962898.gateway_id: "" => "nat-06bd9ef37d96ac470"
route.2863962898.nat_gateway_id: "" => ""

In your configuration, you're providing a NAT Gateway ID to the gateway_id attribute. Changing your config to use this:

  route {
    cidr_block     = "0.0.0.0/0"
    nat_gateway_id = "${element(aws_nat_gateway.nat.*.id, count.index)}"
  }

will resolve the issue here.

catsby on 30 Jun 2016

👍2

+1 Thank you

rjinski on 30 Jun 2016

I'm going to lock this issue because it has been closed for _30 days_ ⏳. This helps our maintainers find and focus on the active issues.

If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.