Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add Nomad workload information to CNI args #24319

Merged
merged 1 commit into from
Nov 19, 2024
Merged

Add Nomad workload information to CNI args #24319

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 3 additions & 0 deletions .changelog/24319.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,3 @@
```release-note:improvement
cni: Add Nomad specific workload information to CNI_ARGS
```
24 changes: 24 additions & 0 deletions client/allocrunner/networking_cni.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -28,6 +28,7 @@ import (
consulIPTables "github.com/hashicorp/consul/sdk/iptables"
log "github.com/hashicorp/go-hclog"
"github.com/hashicorp/go-set/v3"
"github.com/hashicorp/nomad/client/taskenv"
"github.com/hashicorp/nomad/helper"
"github.com/hashicorp/nomad/helper/envoy"
"github.com/hashicorp/nomad/nomad/structs"
Expand Down Expand Up @@ -117,6 +118,26 @@ func addCustomCNIArgs(networks []*structs.NetworkResource, cniArgs map[string]st
}
}

func addNomadWorkloadCNIArgs(logger log.Logger, alloc *structs.Allocation, cniArgs map[string]string) {
for key, value := range map[string]string{
// these are the very same keys that are used to build task env vars
taskenv.Region: alloc.Job.Region, // NOMAD_REGION
taskenv.Namespace: alloc.Namespace, // NOMAD_NAMESPACE
taskenv.JobID: alloc.Job.ID, // NOMAD_JOB_ID
taskenv.GroupName: alloc.TaskGroup, // NOMAD_GROUP_NAME
taskenv.AllocID: alloc.ID, // NOMAD_ALLOC_ID
} {
// job ID and group name may contain ";" but CNI_ARGS are ";"-separated
// per the spec, so they may not be used in arg keys or values.
if strings.Contains(value, ";") {
logger.Warn("Skipping CNI arg because it contains a semicolon",
"key", key, "value", value)
} else {
cniArgs[key] = value
}
}
}

// Setup calls the CNI plugins with the add action
func (c *cniNetworkConfigurator) Setup(ctx context.Context, alloc *structs.Allocation, spec *drivers.NetworkIsolationSpec) (*structs.AllocNetworkStatus, error) {
if err := c.ensureCNIInitialized(); err != nil {
Expand All @@ -133,6 +154,9 @@ func (c *cniNetworkConfigurator) Setup(ctx context.Context, alloc *structs.Alloc

addCustomCNIArgs(tg.Networks, cniArgs)

// Add NOMAD_* after custom args so it cannot be overridden.
addNomadWorkloadCNIArgs(c.logger, alloc, cniArgs)

portMaps := getPortMapping(alloc, c.ignorePortMappingHostIP)

tproxyArgs, err := c.setupTransparentProxyArgs(alloc, spec, portMaps)
Expand Down
49 changes: 44 additions & 5 deletions client/allocrunner/networking_cni_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -137,7 +137,12 @@ func TestSetup(t *testing.T) {
Address: "99.99.99.99",
},
expectArgs: map[string]string{
"IgnoreUnknown": "true",
"IgnoreUnknown": "true",
"NOMAD_ALLOC_ID": "7cd08c6c-86c8-0bfa-f7ca-338466447711",
"NOMAD_GROUP_NAME": "web",
"NOMAD_JOB_ID": "mock-service",
"NOMAD_NAMESPACE": "default",
"NOMAD_REGION": "global",
},
},
{
Expand All @@ -148,7 +153,12 @@ func TestSetup(t *testing.T) {
Address: "99.99.99.99",
},
expectArgs: map[string]string{
"IgnoreUnknown": "true",
"IgnoreUnknown": "true",
"NOMAD_ALLOC_ID": "7cd08c6c-86c8-0bfa-f7ca-338466447711",
"NOMAD_GROUP_NAME": "web",
"NOMAD_JOB_ID": "mock-service",
"NOMAD_NAMESPACE": "default",
"NOMAD_REGION": "global",
},
},
{
Expand All @@ -174,9 +184,31 @@ func TestSetup(t *testing.T) {
Address: "99.99.99.99",
},
expectArgs: map[string]string{
"IgnoreUnknown": "true",
"first_arg": "example",
"new_arg": "example_2",
"IgnoreUnknown": "true",
"first_arg": "example",
"new_arg": "example_2",
"NOMAD_ALLOC_ID": "7cd08c6c-86c8-0bfa-f7ca-338466447711",
"NOMAD_GROUP_NAME": "web",
"NOMAD_JOB_ID": "mock-service",
"NOMAD_NAMESPACE": "default",
"NOMAD_REGION": "global",
},
},
{
name: "cni workload with invalid job id and namespace",
modAlloc: func(a *structs.Allocation) {
a.Job.ID = "this;does;not;work"
a.Namespace = "no;chance"
},
expectResult: &structs.AllocNetworkStatus{
InterfaceName: "eth0",
Address: "99.99.99.99",
},
expectArgs: map[string]string{
"IgnoreUnknown": "true",
"NOMAD_ALLOC_ID": "7cd08c6c-86c8-0bfa-f7ca-338466447711",
"NOMAD_GROUP_NAME": "web",
"NOMAD_REGION": "global",
},
},
{
Expand Down Expand Up @@ -215,6 +247,11 @@ func TestSetup(t *testing.T) {
"IgnoreUnknown": "true",
"extra_arg": "example",
"CONSUL_IPTABLES_CONFIG": `{"ConsulDNSIP":"192.168.1.117","ConsulDNSPort":8600,"ProxyUserID":"101","ProxyInboundPort":9999,"ProxyOutboundPort":15001,"ExcludeInboundPorts":["9002"],"ExcludeOutboundPorts":null,"ExcludeOutboundCIDRs":null,"ExcludeUIDs":null,"NetNS":"/var/run/docker/netns/nonsense-ns","IptablesProvider":null}`,
"NOMAD_ALLOC_ID": "7cd08c6c-86c8-0bfa-f7ca-338466447711",
"NOMAD_GROUP_NAME": "web",
"NOMAD_JOB_ID": "mock-service",
"NOMAD_NAMESPACE": "default",
"NOMAD_REGION": "global",
},
},
}
Expand Down Expand Up @@ -246,6 +283,8 @@ func TestSetup(t *testing.T) {
}

alloc := mock.ConnectAlloc()
alloc.ID = "7cd08c6c-86c8-0bfa-f7ca-338466447711" // Fix the ID for easier testing
alloc.Job.ID = "mock-service" // Fix the ID for easier testing
if tc.modAlloc != nil {
tc.modAlloc(alloc)
}
Expand Down
9 changes: 7 additions & 2 deletions website/content/docs/networking/cni.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -250,8 +250,13 @@ To specify that a job should use a CNI network, set the task group's network
that have fingerprinted a CNI configuration with the given name. For example, to
use the configuration named `mynet`, you should set the task group's network
mode to `cni/mynet`. Nodes that have a network configuration defining a network
named `mynet` in their `cni_config_dir` are eligible to run the workload.

named `mynet` in their `cni_config_dir` are eligible to run the workload. Nomad
additionally supplies the following arguments via `CNI_ARGS` to the CNI network:
`NOMAD_REGION`, `NOMAD_NAMESPACE`, `NOMAD_JOB_ID`, `NOMAD_GROUP_NAME`, and
`NOMAD_ALLOC_ID`. Since the `CNI_ARGS` do not allow values to contain a semicolon
Nomad will not set keys where the value contains a semicolon (this could happen
with the job ID). CNI plugins utilizing `NOMAD_*` CNI arguments are advised to
apply a defensive policy or simply error out.

[cni-spec]: https://www.cni.dev/docs/spec/
[cni-plugin-docs]: https://www.cni.dev/plugins/current/
Expand Down