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Merge pull request #1366 from reactiveops/kris-and-eric-1282 

Specify Existing NAT Gateways to Use in Cluster Creation
This commit is contained in:
Justin Santa Barbara 2017-01-19 21:06:12 -05:00 committed by GitHub
parent 211d6bf0d5 1e3d94392c
commit a60e10eacd
16 changed files with 468 additions and 73 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
cmd/kops/create_cluster_integration_test.go
View File

@ -18,6 +18,7 @@ package main
import (
"bytes"
//"fmt"
"github.com/golang/glog"
"io/ioutil"
"k8s.io/kops/cmd/kops/util"
@ -51,6 +52,12 @@ func TestCreateClusterPrivate(t *testing.T) {
runCreateClusterIntegrationTest(t, "../../tests/integration/create_cluster/private", "v1alpha2")
}
// TestCreateClusterPrivate runs kops create cluster private.example.com --zones us-test-1a --master-zones us-test-1a
//func TestCreateClusterWithNGWSpecified(t *testing.T) {
// runCreateClusterIntegrationTest(t, "../../tests/integration/create_cluster/ngwspecified", "v1alpha1")
// runCreateClusterIntegrationTest(t, "../../tests/integration/create_cluster/ngwspecified", "v1alpha2")
//}
func runCreateClusterIntegrationTest(t *testing.T, srcDir string, version string) {
var stdout bytes.Buffer

2
cmd/kops/update_cluster.go
View File

@ -156,7 +156,9 @@ func RunUpdateCluster(f *util.Factory, clusterName string, out io.Writer, c *Upd
DryRun: isDryrun,
MaxTaskDuration: c.MaxTaskDuration,
}
err = applyCmd.Run()
if err != nil {
return err
}

6
docs/aws.md
View File

@ -74,8 +74,6 @@ aws configure # Input your credentials here
aws iam list-users
```
PyPi is the officially supported `aws cli` download avenue, and kops suggests using it. [More information](https://pypi.python.org/pypi/awscli) on the package.
#### Other Platforms
Official documentation [here](http://docs.aws.amazon.com/cli/latest/userguide/installing.html)
@ -241,7 +239,9 @@ kubectl -n kube-system get po
## What's next?
Kops has a ton of great features, and an amazing support team. We recommend researching [other interesting modes](commands.md#other-interesting-modes) to learn more about generating Terraform configurations, or running your cluster in HA (Highly Available). Also be sure to check out how to run a [private network topology](topology.md) in AWS.
Kops has a ton of great features, and an amazing support team. We recommend researching [other interesting modes](commands.md#other-interesting-modes) to learn more about generating Terraform configurations, or running your cluster in HA (Highly Available). You might want to take a peek at the [cluster spec docs](cluster_spec.md) for helping to configure these "other interesting modes". Also be sure to check out how to run a [private network topology](topology.md) in AWS.
Explore the program, and work on getting your `cluster config` hammered out!

25
docs/cluster_spec.md
View File

@ -55,6 +55,31 @@ spec:
- 12.34.56.78/32
```
### cluster.spec Subnet Keys
#### id
ID of a subnet to share in an existing VPC.
#### egress
The resource identifier (ID) of something in your existing VPC that you would like to use as "egress" to the outside world. This feature was originally envisioned to allow re-use of NAT Gateways. In this case, the correct usageis as follows.
```
spec:
subnets:
- cidr: 10.20.64.0/21
name: us-east-1a
egress: nat-987654321
type: Private
zone: us-east-1a
- cidr: 10.20.32.0/21
name: utility-us-east-1a
id: subnet-12345
type: Utility
zone: us-east-1a
```
### kubeAPIServer
This block contains configuration for the `kube-apiserver`.

62
docs/run_in_existing_vpc.md
View File

@ -9,12 +9,14 @@ Use kops create cluster with the `--vpc` and `--network-cidr` arguments for your
```
export KOPS_STATE_STORE=s3://<somes3bucket>
export CLUSTER_NAME=<sharedvpc.mydomain.com>
export VPC_ID=vpc-12345678 # replace with your VPC id
export NETWORK_CIDR=10.100.0.0/16 # replace with the cidr for the VPC ${VPC_ID}
kops create cluster --zones=us-east-1b --name=${CLUSTER_NAME} \
--vpc=vpc-a80734c1 --network-cidr=10.100.0.0/16
--vpc=${VPC_ID} --network-cidr=${NETWORK_CIDR}
```
Then `kops edit cluster ${CLUSTER_NAME}` should show you something like:
Then `kops edit cluster ${CLUSTER_NAME}` will show you something like:
```
metadata:
@ -22,12 +24,14 @@ metadata:
name: ${CLUSTER_NAME}
spec:
cloudProvider: aws
networkCIDR: 10.100.0.0/16
networkID: vpc-a80734c1
networkCIDR: ${NETWORK_CIDR}
networkID: ${VPC_ID}
nonMasqueradeCIDR: 100.64.0.0/10
zones:
- cidr: 10.100.32.0/19
name: eu-central-1a
subnets:
- cidr: 172.20.32.0/19
name: us-east-1b
type: Public
zone: us-east-1b
```
@ -74,11 +78,13 @@ probably remove that tag to indicate that the resources are not owned by that cl
deleting the cluster won't try to delete the VPC. (Deleting the VPC won't succeed anyway, because it's in use,
but it's better to avoid the later confusion!)
## Running in a shared subnet
## Advanced Options for Creating Clusters in Existing VPCs
You can also use a shared subnet. Doing so is not recommended unless you are using external networking ([kope-routing](https://github.com/kopeio/kope-routing)).
### Shared Subnets
Edit your cluster to add the ID of the subnet:
`kops` can create a cluster in shared subnets in both public and private network [topologies](docs/topology.md). Doing so is not recommended unless you are using [external networking](docs/networking.md#supported-cni-networking)
After creating a basic cluster spec, edit your cluster to add the ID of the subnet:
`kops edit cluster ${CLUSTER_NAME}`
@ -88,13 +94,15 @@ metadata:
name: ${CLUSTER_NAME}
spec:
cloudProvider: aws
networkCIDR: 10.100.0.0/16
networkID: vpc-a80734c1
networkCIDR: ${NETWORK_CIDR}
networkID: ${VPC_ID}
nonMasqueradeCIDR: 100.64.0.0/10
zones:
- cidr: 10.100.32.0/19
name: eu-central-1a
id: subnet-1234567 # Replace this with the ID of your subnet
subnets:
- cidr: 172.20.32.0/19
name: us-east-1b
id: subnet-id123
type: Public
zone: us-east-1b
```
Make sure that the CIDR matches the CIDR of your subnet. Then update your cluster through the normal update procedure:
@ -104,3 +112,25 @@ kops update cluster ${CLUSTER_NAME}
# Review changes
kops update cluster ${CLUSTER_NAME} --yes
```
### Shared NAT Gateways
On AWS in private [topology](docs/topology.md), `kops` creates one NAT Gateway (NGW) per AZ. If your shared VPC is already set up with an NGW in the subnet that `kops` deploys private resources to, it is possible to specify the ID and have `kops`/`kubernetes` use it.
After creating a basic cluster spec, edit your cluster to specify NGW:
`kops edit cluster ${CLUSTER_NAME}`
```yaml
spec:
subnets:
- cidr: 10.20.64.0/21
name: us-east-1a
egress: nat-987654321
type: Private
zone: us-east-1a
- cidr: 10.20.32.0/21
name: utility-us-east-1a
type: Utility
zone: us-east-1a
```

2
pkg/apis/kops/cluster.go
View File

@ -322,6 +322,8 @@ type ClusterSubnetSpec struct {
// ProviderID is the cloud provider id for the objects associated with the zone (the subnet on AWS)
ProviderID string `json:"id,omitempty"`
Egress string `json:"egress,omitempty"`
Type SubnetType `json:"type,omitempty"`
}

1
pkg/apis/kops/parse.go
View File

@ -46,6 +46,7 @@ func ParseInstanceGroupRole(input string, lenient bool) (InstanceGroupRole, bool
// ParseRawYaml parses an object just using yaml, without the full api machinery
// Deprecated: prefer using the API machinery
func ParseRawYaml(data []byte, dest interface{}) error {
// Yaml can't parse empty strings
configString := string(data)
configString = strings.TrimSpace(configString)

3
pkg/apis/kops/v1alpha2/cluster.go
View File

@ -228,5 +228,6 @@ type ClusterSubnetSpec struct {
// ProviderID is the cloud provider id for the objects associated with the zone (the subnet on AWS)
ProviderID string `json:"id,omitempty"`
Type SubnetType `json:"type,omitempty"`
Egress string `json:"egress,omitempty"`
Type SubnetType `json:"type,omitempty"`
}

8
pkg/apis/kops/validation.go
View File

@ -332,6 +332,14 @@ func (c *Cluster) Validate(strict bool) error {
}
}
// Egress specification support
{
for _, s := range c.Spec.Subnets {
if s.Egress != "" && !(strings.Contains("nat-", s.Egress)) {
return fmt.Errorf("egress must be of type NAT Gateway")
}
}
}
// Etcd
{

74
pkg/model/network.go
View File

@ -22,6 +22,7 @@ import (
"k8s.io/kops/upup/pkg/fi"
"k8s.io/kops/upup/pkg/fi/cloudup/awstasks"
"k8s.io/kubernetes/pkg/util/sets"
"strings"
)
// NetworkModelBuilder configures network objects
@ -32,6 +33,7 @@ type NetworkModelBuilder struct {
var _ fi.ModelBuilder = &NetworkModelBuilder{}
func (b *NetworkModelBuilder) Build(c *fi.ModelBuilderContext) error {
sharedVPC := b.Cluster.SharedVPC()
// VPC that holds everything for the cluster
@ -112,6 +114,7 @@ func (b *NetworkModelBuilder) Build(c *fi.ModelBuilderContext) error {
CIDR: s(subnetSpec.CIDR),
Shared: fi.Bool(sharedSubnet),
}
if subnetSpec.ProviderID != "" {
subnet.ID = s(subnetSpec.ProviderID)
}
@ -148,36 +151,63 @@ func (b *NetworkModelBuilder) Build(c *fi.ModelBuilderContext) error {
}
}
for _, zone := range privateZones.List() {
// Loop over zones
for i, zone := range privateZones.List() {
utilitySubnet, err := b.LinkToUtilitySubnetInZone(zone)
if err != nil {
return err
}
// Every NGW needs a public (Elastic) IP address, every private
// subnet needs a NGW, lets create it. We tie it to a subnet
// so we can track it in AWS
eip := &awstasks.ElasticIP{
Name: s(zone + "." + b.ClusterName()),
AssociatedNatGatewayRouteTable: b.LinkToPrivateRouteTableInZone(zone),
}
c.AddTask(eip)
var ngw = &awstasks.NatGateway{}
if b.Cluster.Spec.Subnets[i].Egress != "" {
if strings.Contains(b.Cluster.Spec.Subnets[i].Egress, "nat-") {
// NAT Gateway
//
// All private subnets will need a NGW, one per zone
//
// The instances in the private subnet can access the Internet by
// using a network address translation (NAT) gateway that resides
// in the public subnet.
ngw := &awstasks.NatGateway{
Name: s(zone + "." + b.ClusterName()),
Subnet: utilitySubnet,
ElasticIP: eip,
ngw = &awstasks.NatGateway{
Name: s(zone + "." + b.ClusterName()),
Subnet: utilitySubnet,
ID: s(b.Cluster.Spec.Subnets[i].Egress),
AssociatedRouteTable: b.LinkToPrivateRouteTableInZone(zone),
// If we're here, it means this NatGateway was specified, so we are Shared
Shared: fi.Bool(true),
}
AssociatedRouteTable: b.LinkToPrivateRouteTableInZone(zone),
c.AddTask(ngw)
} else {
return fmt.Errorf("kops currently only supports re-use of NAT Gateways. We will support more eventually! Please see https://github.com/kubernetes/kops/issues/1530")
}
} else {
// Every NGW needs a public (Elastic) IP address, every private
// subnet needs a NGW, lets create it. We tie it to a subnet
// so we can track it in AWS
var eip = &awstasks.ElasticIP{}
eip = &awstasks.ElasticIP{
Name: s(zone + "." + b.ClusterName()),
AssociatedNatGatewayRouteTable: b.LinkToPrivateRouteTableInZone(zone),
}
c.AddTask(eip)
// NAT Gateway
//
// All private subnets will need a NGW, one per zone
//
// The instances in the private subnet can access the Internet by
// using a network address translation (NAT) gateway that resides
// in the public subnet.
//var ngw = &awstasks.NatGateway{}
ngw = &awstasks.NatGateway{
Name: s(zone + "." + b.ClusterName()),
Subnet: utilitySubnet,
ElasticIP: eip,
AssociatedRouteTable: b.LinkToPrivateRouteTableInZone(zone), // Unsure about this?
}
c.AddTask(ngw)
}
c.AddTask(ngw)
// Private Route Table
//

90
tests/integration/create_cluster/ngwspecified/expected-v1alpha1.yaml Normal file
View File

@ -0,0 +1,90 @@
apiVersion: kops/v1alpha1
kind: Cluster
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: private.example.com
spec:
api:
loadBalancer:
type: Public
channel: stable
cloudProvider: aws
configBase: memfs://tests/private.example.com
etcdClusters:
- etcdMembers:
- name: us-test-1a
zone: us-test-1a
name: main
- etcdMembers:
- name: us-test-1a
zone: us-test-1a
name: events
kubernetesVersion: v1.4.7
masterPublicName: api.private.example.com
networkCIDR: 172.20.0.0/16
networking:
kopeio: {}
nonMasqueradeCIDR: 100.64.0.0/10
topology:
bastion:
enable: true
name: bastion.private.example.com
dns:
type: Public
masters: private
nodes: private
zones:
- cidr: 172.20.0.0/22
name: us-test-1a
privateCIDR: 172.20.32.0/19
---
apiVersion: kops/v1alpha1
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: bastions
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: t2.micro
maxSize: 1
minSize: 1
role: Bastion
zones:
- utility-us-test-1a
---
apiVersion: kops/v1alpha1
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: master-us-test-1a
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: m3.medium
maxSize: 1
minSize: 1
role: Master
zones:
- us-test-1a
---
apiVersion: kops/v1alpha1
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: nodes
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: t2.medium
maxSize: 2
minSize: 2
role: Node
zones:
- us-test-1a

96
tests/integration/create_cluster/ngwspecified/expected-v1alpha2.yaml Normal file
View File

@ -0,0 +1,96 @@
apiVersion: kops/v1alpha2
kind: Cluster
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: private.example.com
spec:
api:
loadBalancer:
type: Public
channel: stable
cloudProvider: aws
configBase: memfs://tests/private.example.com
etcdClusters:
- etcdMembers:
- instanceGroup: master-us-test-1a
name: us-test-1a
name: main
- etcdMembers:
- instanceGroup: master-us-test-1a
name: us-test-1a
name: events
kubernetesVersion: v1.4.7
masterPublicName: api.private.example.com
networkCIDR: 172.20.0.0/16
networking:
kopeio: {}
nonMasqueradeCIDR: 100.64.0.0/10
subnets:
- cidr: 172.20.32.0/19
name: us-test-1a
ngwEip: eipalloc-e12345
ngwId: nat-09123456
type: Private
zone: us-test-1a
- cidr: 172.20.0.0/22
name: utility-us-test-1a
type: Utility
zone: us-test-1a
topology:
bastion:
bastionPublicName: bastion.private.example.com
dns:
type: Public
masters: private
nodes: private
---
apiVersion: kops/v1alpha2
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: bastions
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: t2.micro
maxSize: 1
minSize: 1
role: Bastion
subnets:
- utility-us-test-1a
---
apiVersion: kops/v1alpha2
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: master-us-test-1a
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: m3.medium
maxSize: 1
minSize: 1
role: Master
subnets:
- us-test-1a
---
apiVersion: kops/v1alpha2
kind: InstanceGroup
metadata:
creationTimestamp: "2017-01-01T00:00:00Z"
name: nodes
spec:
associatePublicIp: true
image: kope.io/k8s-1.4-debian-jessie-amd64-hvm-ebs-2016-10-21
machineType: t2.medium
maxSize: 2
minSize: 2
role: Node
subnets:
- us-test-1a

8
tests/integration/create_cluster/ngwspecified/options.yaml Normal file
View File

@ -0,0 +1,8 @@
ClusterName: private.example.com
Zones: us-test-1a
Cloud: aws
Topology: private
Networking: kopeio-vxlan
Bastion: true
NgwEips: eipalloc-e12345
NgwIds: nat-09123456

74
upup/pkg/fi/cloudup/awstasks/natgateway.go
View File

@ -34,6 +34,11 @@ type NatGateway struct {
Subnet *Subnet
ID *string
EgressId *string
// Shared is set if this is a shared NatGateway
Shared *bool
// We can't tag NatGateways, so we have to find through a surrogate
AssociatedRouteTable *RouteTable
}
@ -45,17 +50,54 @@ func (e *NatGateway) CompareWithID() *string {
}
func (e *NatGateway) Find(c *fi.Context) (*NatGateway, error) {
ngw, err := e.findNatGateway(c)
if err != nil {
return nil, err
}
if ngw == nil {
return nil, nil
cloud := c.Cloud.(awsup.AWSCloud)
var ngw *ec2.NatGateway
actual := &NatGateway{}
if e.ID != nil && *e.ID != "" {
// We have an existing NGW, lets look up the EIP
var ngwIds []*string
ngwIds = append(ngwIds, e.ID)
request := &ec2.DescribeNatGatewaysInput{
NatGatewayIds: ngwIds,
}
response, err := cloud.EC2().DescribeNatGateways(request)
if err != nil {
return nil, fmt.Errorf("error listing Nat Gateways %v", err)
}
if len(response.NatGateways) != 1 {
return nil, fmt.Errorf("found %b NAT Gateways, expected 1", len(response.NatGateways))
}
if len(response.NatGateways) == 1 {
ngw = response.NatGateways[0]
}
if len(response.NatGateways[0].NatGatewayAddresses) != 1 {
return nil, fmt.Errorf("found %b EIP Addresses for 1 NAT Gateway, expected 1", len(response.NatGateways))
}
if len(response.NatGateways[0].NatGatewayAddresses) == 1 {
actual.ElasticIP = &ElasticIP{ID: response.NatGateways[0].NatGatewayAddresses[0].AllocationId}
}
} else {
// This is the normal/default path
ngw, err := e.findNatGateway(c)
if err != nil {
return nil, err
}
if ngw == nil {
return nil, nil
}
}
actual := &NatGateway{
ID: ngw.NatGatewayId,
}
actual.ID = ngw.NatGatewayId
actual.Subnet = e.Subnet
if len(ngw.NatGatewayAddresses) == 0 {
// Not sure if this ever happens
@ -233,6 +275,7 @@ func (e *NatGateway) waitAvailable(cloud awsup.AWSCloud) error {
func (_ *NatGateway) RenderAWS(t *awsup.AWSAPITarget, a, e, changes *NatGateway) error {
// New NGW
var id *string
if a == nil {
glog.V(2).Infof("Creating Nat Gateway")
@ -262,8 +305,19 @@ func (_ *NatGateway) RenderAWS(t *awsup.AWSAPITarget, a, e, changes *NatGateway)
tags["AssociatedNatgateway"] = *id
err := t.AddAWSTags(*e.Subnet.ID, tags)
if err != nil {
return fmt.Errorf("Unable to tag subnet %v", err)
return fmt.Errorf("unable to tag subnet %v", err)
}
// If this is a shared NGW, we need to tag it
// The tag that implies "shared" is `AssociatedNatgateway`=> NGW-ID
// This is better than just a tag that's shared because this lets us create a whitelist of these NGWs
// without doing a bunch more work in `kutil/delete_cluster.go`
if *e.Shared == true {
glog.V(2).Infof("tagging route table %s to track shared NGW", *e.AssociatedRouteTable.ID)
err = t.AddAWSTags(*e.AssociatedRouteTable.ID, tags)
}
return nil
}

5
upup/pkg/fi/cloudup/defaults.go
View File

@ -28,6 +28,11 @@ import (
// For example, it assigns stable Keys to InstanceGroups & Masters, and
// it assigns CIDRs to subnets
// We also assign KubernetesVersion, because we want it to be explicit
//
// PerformAssignments is called on create, as well as an update. In fact
// any time Run() is called in apply_cluster.go we will reach this function.
// Please do all after-market logic here.
//
func PerformAssignments(c *kops.Cluster) error {
// Topology support

78
upup/pkg/kutil/delete_cluster.go
View File

@ -921,10 +921,33 @@ func ListSubnets(cloud fi.Cloud, clusterName string) ([]*ResourceTracker, error)
}
// Associated Nat Gateways
// Note: Jan 2017 @geojaz we musn't delete any shared NAT Gateways here.
// Since we don't have tagging on the NGWs, we have to read the route tables
if len(ngws) != 0 {
rtRequest := &ec2.DescribeRouteTablesInput{}
rtResponse, err := c.EC2().DescribeRouteTables(rtRequest)
// sharedNgwIds is like a whitelist for shared Ngws that we can ensure are not deleted
sharedNgwIds := sets.NewString()
{
for _, rt := range rtResponse.RouteTables {
for _, t := range rt.Tags {
k := *t.Key
v := *t.Value
if k == "AssociatedNatgateway" {
sharedNgwIds.Insert(v)
}
}
}
}
glog.V(2).Infof("Querying Nat Gateways")
request := &ec2.DescribeNatGatewaysInput{}
response, err := c.EC2().DescribeNatGateways(request)
if err != nil {
return nil, fmt.Errorf("error describing NatGateways: %v", err)
}
@ -934,6 +957,10 @@ func ListSubnets(cloud fi.Cloud, clusterName string) ([]*ResourceTracker, error)
if !ngws[id] {
continue
}
if sharedNgwIds.Has(id) {
// If we find this NGW in our whitelist- skip it (don't delete!)
continue
}
tracker := &ResourceTracker{
Name: id,
@ -1431,7 +1458,6 @@ func FindNatGateways(cloud fi.Cloud, routeTableIds sets.String) ([]*ResourceTrac
c := cloud.(awsup.AWSCloud)
natGatewayIds := sets.NewString()
{
request := &ec2.DescribeRouteTablesInput{}
for routeTableId := range routeTableIds {
@ -1441,33 +1467,43 @@ func FindNatGateways(cloud fi.Cloud, routeTableIds sets.String) ([]*ResourceTrac
if err != nil {
return nil, fmt.Errorf("error from DescribeRouteTables: %v", err)
}
shared := false
for _, rt := range response.RouteTables {
for _, route := range rt.Routes {
if route.NatGatewayId != nil {
natGatewayIds.Insert(*route.NatGatewayId)
shared = false
for _, t := range rt.Tags {
k := *t.Key
// v := *t.Value
if k == "AssociatedNatgateway" {
shared = true
}
}
if shared == false {
for _, route := range rt.Routes {
if route.NatGatewayId != nil {
natGatewayIds.Insert(*route.NatGatewayId)
fmt.Printf("inserting %s to be deleted\n", *route.NatGatewayId)
}
}
}
}
}
{
// We could do this to find if a NAT gateway is shared
//request := &ec2.DescribeRouteTablesInput{}
//request.Filters = append(request.Filters, awsup.NewEC2Filter("route.nat-gateway-id", natGatewayId))
//response, err := c.EC2().DescribeRouteTables(request)
//if err != nil {
// return fmt.Errorf("error from DescribeRouteTables: %v", err)
//}
//
//for _, rt := range response.RouteTables {
// routeTableId := aws.StringValue(rt.RouteTableId)
//}
}
// I think this is now out of date. @geojaz 1/2017
//{
// // We could do this to find if a NAT gateway is shared
//
// request := &ec2.DescribeRouteTablesInput{}
// request.Filters = append(request.Filters, awsup.NewEC2Filter("route.nat-gateway-id", natGatewayIds[0]))
// response, err := c.EC2().DescribeRouteTables(request)
// if err != nil {
// return fmt.Errorf("error from DescribeRouteTables: %v", err)
// }
//
// for _, rt := range response.RouteTables {
// routeTableId := aws.StringValue(rt.RouteTableId)
// }
//}
var trackers []*ResourceTracker
if len(natGatewayIds) != 0 {
request := &ec2.DescribeNatGatewaysInput{}
for natGatewayId := range natGatewayIds {