This page describes the specialized Network Function Kubernetes operator that Google Distributed Cloud connected ships with. This operator implements a set of CustomResourceDefinitions (CRDs) that allow Distributed Cloud connected to execute high-performance workloads.
The Network Function operator lets you do the following:
- Poll for existing network devices on a node.
- Query the IP address and physical link state for each network device on a node.
- Provision additional network interfaces on a node.
- Configure low-level system features on the node's physical machine required to support high-performance workloads.
Network Function operator profiles
Distributed Cloud connected provides the following Network Function operator functionality:
-
Network automationfunctions let you automate the configuration of your workload Pod networking.
-
State exportfunctions let you export host network states to the user, including network interface configuration and status.
-
Webhookfunctions let you validate user inputs.
Prerequisites
The Network Function operator fetches network configuration from the Distributed Cloud Edge Network API.
To allow this, you must grant the Network Function operator service account the Edge Network Viewer role
( roles/edgenetwork.viewer
) using the following command:
gcloud projects add-iam-policy-binding ZONE_PROJECT_ID \ --role roles/edgenetwork.viewer \ --member "serviceAccount: CLUSTER_PROJECT_ID .svc.id.goog[nf-operator/nf-angautomator-sa]"
Replace the following:
-
ZONE_PROJECT_IDwith the ID of the Google Cloud project that holds the Distributed Cloud Edge Network API resources. -
CLUSTER_PROJECT_IDwith the ID of the Google Cloud project that holds the target Distributed Cloud connected cluster.
Network Function operator resources
The Distributed Cloud connected Network Function operator implements the following Kubernetes CRDs:
-
Network. Defines a virtual network that pods can use to communicate with internal and external resources. You must create the corresponding VLAN using the Distributed Cloud Edge Network API before specifying it in this resource. For instructions, see Create a subnetwork . -
NetworkInterfaceState. Enables the discovery of network interface states and querying a network interface for link state and IP address. -
NodeSystemConfigUpdate. Enables the configuration of low-level system features such as kernel options andKubeletflags. -
NetworkAttachmentDefinition. Lets you attach Distributed Cloud pods to one or more logical or physical networks on your Distributed Cloud connected node. You must create the corresponding VLAN using the Distributed Cloud Edge Network API before specifying it in this resource. For instructions, see Create a subnetwork .
The Network Function operator also lets you define secondary network interfaces.
Network
resource
The Network
resource defines a virtual network within your
Distributed Cloud connected deployment that pods within your
Distributed Cloud connected cluster can use to communicate with
internal and external resources.
The Network
resource provides the following configurable parameters for the
network interface exposed as writable fields:
-
spec.type: specifies the network transport layer for this network. The only valid value isL2. You must also specify anodeInterfaceMatcher.interfaceNamevalue. -
spec.nodeInterfaceMatcher.interfaceName: the name of the physical network interface on the target Distributed Cloud connected node to use with this network. -
spec.gateway4: the IP address of the network gateway for this network. -
spec.l2NetworkConfig.prefixLength4: specifies the CIDR range for this network. -
annotations.networking.gke.io/gdce-per-node-ipam-size: specifies the subnet mask size for an individual node. If this is omitted, the subnet mask size is set to the value of thecluster-cidr-config-per-node-mask-sizefield in thenf-operator-defaultsConfigMap in thenf-operatornamespace. -
annotations.networking.gke.io/gke-gateway-clusterip-cidr: specifies a CIDR block for accessing clusters through Connect gateway. This is used byCoreDNSon secondary network interfaces. -
annotations.networking.gke.io/gke-gateway-pod-cidr: specifies a CIDR block for a Pod that can be allocated on secondary network interfaces. -
annotations.networking.gke.io/gdce-vlan-id: specifies the VLAN ID for this network. -
annotations.networking.gke.io/gdce-vlan-mtu: (optional) specifies the MTU value for this network. If omitted, inherits the MTU value from the parent interface. -
annotations.networking.gke.io/gdce-lb-service-vip-cidr: specifies the virtual IP address range for the load balancing service. The value can be a CIDR block or an explicit address range value. This annotation is mandatory for Layer 3 and optional for Layer 2 load balancing.
The following example illustrates the structure of the resource:
apiVersion
:
networking
.
gke
.
io
/
v1
kind
:
Network
metadata
:
name
:
vlan200
-
network
annotations
:
networking
.
gke
.
io
/
gdce
-
vlan
-
id
:
200
networking
.
gke
.
io
/
gdce
-
vlan
-
mtu
:
1500
networking
.
gke
.
io
/gdce-lb-service-vip-cidrs: "10.1.1.0/
24
"
spec
:
type
:
L2
nodeInterfaceMatcher
:
interfaceName
:
gdcenet0
.
200
gateway4
:
10.53
.
0.1
To specify multiple virtual IP address ranges for the load balancing service, use
the networking.gke.io/gdce-lb-service-vip-cidrs
annotation. You can provide
the values for this annotation as either a comma-separated list or as a JSON payload.
For example:
[
{
"name"
:
"test-oam-3"
,
"addresses"
:
[
"10.235.128.133-10.235.128.133"
],
"autoAssign"
:
false
}
,
{
"name"
:
"test-oam-4"
,
"addresses"
:
[
"10.235.128.134-10.235.128.134"
],
"autoAssign"
:
false
},
{
"name"
:
"test-oam-5"
,
"addresses"
:
[
"10.235.128.135-10.235.128.135"
],
"autoAssign"
:
false
}
]
If you choose to use a JSON payload, we recommend that you use the condensed JSON format. For example:
apiVersion
:
networking.gke.io/v1
kind
:
Network
metadata
:
annotations
:
networking.gke.io/gdce-lb-service-vip-cidrs
:
'[{"name":"test-oam-3","addresses":["10.235.128.133-10.235.128.133"],"autoAssign":false},{"name":"test-oam-4","addresses":["10.235.128.134-10.235.128.134"],"autoAssign":false},{"name":"test-oam-5","addresses":["10.235.128.135-10.235.128.135"],"autoAssign":false}]'
networking.gke.io/gdce-vlan-id
:
"81"
name
:
test-network-vlan81
spec
:
IPAMMode
:
Internal
dnsConfig
:
nameservers
:
-
8.8.8.8
gateway4
:
192.168.81.1
l2NetworkConfig
:
prefixLength4
:
24
nodeInterfaceMatcher
:
interfaceName
:
gdcenet0.81
type
:
L2
Keep in mind that the autoAssign
field defaults to false
if omitted.
NetworkInterfaceState
resource
The NetworkInterfaceState
resource is a read-only resource that lets you
discover physical network interfaces on the node and collect runtime statistics
on the network traffic flowing through those interfaces.
Distributed Cloud creates a NetworkInterfaceState
resource
for each node in a cluster.
The default configuration of Distributed Cloud connected machines
includes a bonded network interface named uplink0
. This interface bonds the eno1np0
and eno2np1
network interfaces. Each of those is connected to one
Distributed Cloud ToR switch, respectively.
The NetworkInterfaceState
resource provides the following categories of
network interface information exposed as read-only status fields.
General information:
-
status.interfaces.ifname: the name of the target network interface. -
status.lastReportTime: the time and date of the last status report for the target interface.
IP address configuration information:
-
status.interfaces.interfaceinfo.address: the IP address assigned to the target interface. -
status.interfaces.interfaceinfo.dns: the IP address of the DNS server assigned to the target interface. -
status.interfaces.interfaceinfo.gateway: the IP address of the network gateway serving the target interface. -
status.interfaces.interfaceinfo.prefixlen: the length of the IP prefix.
Hardware information:
-
status.interfaces.linkinfo.broadcast: the broadcast MAC address of the target interface. -
status.interfaces.linkinfo.businfo: the PCIe device path inbus:slot.functionformat. -
status.interfaces.linkinfo.flags: the interface flags—for example,BROADCAST. -
status.interfaces.linkinfo.macAddress: the Unicast MAC address of the target interface. -
status.interfaces.linkinfo.mtu: the MTU value for the target interface.
Reception statistics:
-
status.interfaces.statistics.rx.bytes: the total bytes received by the target interface. -
status.interfaces.statistics.rx.dropped: the total packets dropped by the target interface. -
status.interfaces.statistics.rx.errors: the total packet receive errors for the target interface. -
status.interfaces.statistics.rx.multicast: the total multicast packets received by the target interface. -
status.interfaces.statistics.rx.overErrors: the total packet receive over errors for the target interface. -
status.interfaces.statistics.rx.packets: the total packets received by the target interface.
Transmission statistics:
-
status.interfaces.statistics.tx.bytes: the total bytes transmitted by the target interface. -
status.interfaces.statistics.tx.carrierErrors: the total carrier errors encountered by the target interface. -
status.interfaces.statistics.tx.collisions: the total packet collisions encountered by the target interface. -
status.interfaces.statistics.tx.dropped: the total packets dropped by the target interface. -
status.interfaces.statistics.tx.errors: the total transmission errors for the target interface. -
status.interfaces.statistics.tx.packets: the total packets transmitted by the target interface.
The following example illustrates the structure of the resource:
apiVersion
:
networking
.
gke
.
io
/
v1
kind
:
NetworkInterfaceState
metadata
:
name
:
MyNode1
nodeName
:
MyNode1
status
:
interfaces
:
-
ifname
:
eno1np0
linkinfo
:
businfo
:
0000
:
1
a
:
00.0
flags
:
up
|
broadcast
|
multicast
macAddress
:
ba
:
16
:
03
:
9
e
:
9
c
:
87
mtu
:
9000
statistics
:
rx
:
bytes
:
1098522811
errors
:
2
multicast
:
190926
packets
:
4988200
tx
:
bytes
:
62157709961
packets
:
169847139
-
ifname
:
eno2np1
linkinfo
:
businfo
:
0000
:
1
a
:
00.1
flags
:
up
|
broadcast
|
multicast
macAddress
:
ba
:
16
:
03
:
9
e
:
9
c
:
87
mtu
:
9000
statistics
:
rx
:
bytes
:
33061895405
multicast
:
110203
packets
:
110447356
tx
:
bytes
:
2370516278
packets
:
11324730
-
ifname
:
enp95s0f0np0
interfaceinfo
:
-
address
:
fe80
::
63
f
:
72
ff
:
fec4
:
2
bf4
prefixlen
:
64
linkinfo
:
businfo
:
0000
:
5
f
:
00.0
flags
:
up
|
broadcast
|
multicast
macAddress
:
04
:
3
f
:
72
:
c4
:
2
b
:
f4
mtu
:
9000
statistics
:
rx
:
bytes
:
37858381
multicast
:
205645
packets
:
205645
tx
:
bytes
:
1207334
packets
:
6542
-
ifname
:
enp95s0f1np1
interfaceinfo
:
-
address
:
fe80
::
63
f
:
72
ff
:
fec4
:
2
bf5
prefixlen
:
64
linkinfo
:
businfo
:
0000
:
5
f
:
00.1
flags
:
up
|
broadcast
|
multicast
macAddress
:
04
:
3
f
:
72
:
c4
:
2
b
:
f5
mtu
:
9000
statistics
:
rx
:
bytes
:
37852406
multicast
:
205607
packets
:
205607
tx
:
bytes
:
1207872
packets
:
6545
-
ifname
:
enp134s0f0np0
interfaceinfo
:
-
address
:
fe80
::
63
f
:
72
ff
:
fec4
:
2
b6c
prefixlen
:
64
linkinfo
:
businfo
:
0000
:
86
:
00.0
flags
:
up
|
broadcast
|
multicast
macAddress
:
04
:
3
f
:
72
:
c4
:
2
b
:
6
c
mtu
:
9000
statistics
:
rx
:
bytes
:
37988773
multicast
:
205584
packets
:
205584
tx
:
bytes
:
1212385
packets
:
6546
-
ifname
:
enp134s0f1np1
interfaceinfo
:
-
address
:
fe80
::
63
f
:
72
ff
:
fec4
:
2
b6d
prefixlen
:
64
linkinfo
:
businfo
:
0000
:
86
:
00.1
flags
:
up
|
broadcast
|
multicast
macAddress
:
04
:
3
f
:
72
:
c4
:
2
b
:
6
d
mtu
:
9000
statistics
:
rx
:
bytes
:
37980702
multicast
:
205548
packets
:
205548
tx
:
bytes
:
1212297
packets
:
6548
-
ifname
:
gdcenet0
interfaceinfo
:
-
address
:
208.117
.
254.36
prefixlen
:
28
-
address
:
fe80
::
b816
:
3
ff
:
fe9e
:
9
c87
prefixlen
:
64
linkinfo
:
flags
:
up
|
broadcast
|
multicast
macAddress
:
ba
:
16
:
03
:
9
e
:
9
c
:
87
mtu
:
9000
statistics
:
rx
:
bytes
:
34160422968
errors
:
2
multicast
:
301129
packets
:
115435591
tx
:
bytes
:
64528301111
packets
:
181171964
..
< remaining
interfaces
omitted
>
lastReportTime
:
"2022-03-30T07:35:44Z"
Configure a secondary interface on a pod using Distributed Cloud multi-networking
Distributed Cloud connected supports creating a secondary network interface on a pod by using its multi-network feature. To do so, complete the following steps:
-
Configure a
Networkresource. For example:apiVersion : networking . gke . io / v1 kind : Network metadata : name : my - network - 410 annotations : networking . gke . io / gdce - vlan - id : "410" networking . gke . io / gdce - lb - service - vip - cidrs : '[{"name":"myPool","addresses":["10.100.63.130-10.100.63.135"],"avoidBuggyIPs":false,"autoAssign":true}]' spec : type : L2 nodeInterfaceMatcher : interfaceName : gdcenet0 . 410 gateway4 : 10.100 . 63.129 l2NetworkConfig : prefixLength4 : 27The
networking.gke.io/gdce-lb-service-vip-cidrsannotation specifies one or more IP address pools for this virtual network. The first half of the CIDR you specify here must include Service Virtual IP (SVIP) addresses. Distributed Cloud connected enforces this requirement through webhook checks as follows:- The SVIP address range must be within the corresponding VLAN CIDR range, and
- The SVIP address range can only span up to the first half of the VLAN CIDR range.
-
Add an annotation to your Distributed Cloud pod definition as follows:
apiVersion : v1 kind : pod metadata : name : myPod annotations : networking . gke . io / interfaces : '[{"interfaceName":"eth0","network":"pod-network"}, {"interfaceName":"eth1","network":"my-network-410"}]' networking . gke . io / default - interface : eth1This annotation configures the
eth0interface as primary and theeth1interface as secondary with Layer2 load balancing with MetalLB.
Configuring your secondary interface as described in this section results in the automatic creation of the following custom resources:
- An
IPAddressPoolresource, which enables automatic SVIP address assignment to Pods. For example:
apiVersion
:
metallb
.
io
/
v1beta1
kind
:
IPAddressPool
metadata
:
name
:
test
-
410
-
pool
namespace
:
kube
-
system
annotations
:
networking
.
gke
.
io
/
network
:
my
-
network
-
410
…
spec
:
addresses
:
-
10.100
.
63.130
-
10.100
.
63.135
autoAssign
:
true
- An
L2Advertisementresource, which enables advertising of the specified SVIP addresses. For example:
apiVersion
:
metallb
.
io
/
v1beta1
kind
:
L2Advertisement
metadata
:
name
:
l2advertise
-
410
namespace
:
kube
-
system
spec
:
ipAddressPools
:
-
test
-
410
-
pool
interfaces
:
-
gdcenet0
.
410
## What's next

