CoreDNS¶
Add-on Overview¶
CoreDNS is a DNS server that uses chain plug-ins to provide domain name resolution services for Kubernetes clusters. It is the recommended DNS server solution by the Kubernetes community.
Add-on Parameters¶
Parameter | Mandatory | Type | Description |
---|---|---|---|
basic | No | object | Basic configuration parameters, which do not need to be specified |
flavor | Yes | Table 2 object | Flavor parameters |
custom | Yes | Table 3 object | Custom parameters |
Parameter | Mandatory | Type | Description |
---|---|---|---|
replicas | Yes | int | Number of pods. The default value is 2. |
resources | Yes | Array of resources object | Container resource (CPU and memory) quotas |
Parameter | Mandatory | Type | Description |
---|---|---|---|
servers | No | object | Configuration of servers |
stub_domains | No | Map<String>[]string | Stub domain configuration |
multiAZEnable | No | bool | Whether to enable the forcible mode of multi-AZ deployment for the deployment component. The default value is false. Deployment pods of the add-on will be forcibly scheduled to nodes in different AZs. If there are fewer AZs than pods, the extra pods will fail to run. If both multiAZEnable and multiAZBalance are set to true, the settings of multiAZBalance take effect, which means, the equivalent mode of multi-AZ deployment is used. |
multiAZBalance | No | bool | Whether to enable the equivalent mode of multi-AZ deployment for the deployment component. The default value is false. Deployment pods of the add-on are evenly scheduled to the nodes in the cluster in each AZ. If a new AZ is added, it is recommended that you increase add-on pods for cross-AZ HA deployment. With the equivalent multi-AZ deployment, the difference between the number of add-on pods in different AZs will be less than or equal to 1. If resources in one of the AZs are insufficient, pods cannot be scheduled to that AZ. |
tolerations | No | Array of Table 5 | Toleration configuration |
Parameter | Mandatory | Type | Description |
---|---|---|---|
limitsCpu | Yes | String | CPU size limit (unit: m) |
limitsMem | Yes | String | Memory size limit (unit: Mi) |
name | Yes | String | Add-on name. The value is fixed at coredns. |
requestsCpu | Yes | String | Requested CPU size (unit: m) |
requestsMem | Yes | String | Requested memory size (unit: Mi) |
Parameter | Mandatory | Type | Description |
---|---|---|---|
key | No | String | Taint key |
effect | No | String | Taint policy |
operator | No | String | Operator |
tolerationSeconds | No | Int | Toleration time window |
Parameter | Mandatory | Type | Description |
---|---|---|---|
port | No | Int | Domain port number. The default value is 5353. |
zones | No | Array of Table 8 | Domain configuration |
plugins | No | Array of Table 7 | Configuration of plugin |
Parameter | Mandatory | Type | Description |
---|---|---|---|
name | Yes | String | Plugin name |
configBlock | No | String | Configuration of plugin |
parameters | No | String/Int | Extended parameters of the plugin |
Parameter | Mandatory | Type | Description |
---|---|---|---|
zone | Yes | String | Domain value. The default value is ".". |
Example Request¶
{
"kind": "Addon",
"apiVersion": "v3",
"metadata": {
"annotations": {
"addon.install/type": "install"
}
},
"spec": {
"clusterID": "2292498e-******-0255ac1001ba",
"version": "1.29.2",
"addonTemplateName": "coredns",
"values": {
"basic": {
"basickey":"val"
},
"flavor": {
"replicas": 2,
"resources": [{
"limitsCpu": "2000m",
"limitsMem": "2000Mi",
"name": "coredns",
"requestsCpu": "2000m",
"requestsMem": "2000Mi"
}]
},
"custom": {
"multiAZBalance": false,
"multiAZEnabled": false,
"node_match_expressions": [],
"servers": [{
"plugins": [{
"name": "bind",
"parameters": "{$POD_IP}"
},
{
"configBlock": "servfail 5s",
"name": "cache",
"parameters": 30
},
{
"name": "errors"
},
{
"name": "health",
"parameters": "{$POD_IP}:8080"
},
{
"name": "ready",
"parameters": "{$POD_IP}:8081"
},
{
"configBlock": "pods insecure\nfallthrough in-addr.arpa ip6.arpa",
"name": "kubernetes",
"parameters": "cluster.local in-addr.arpa ip6.arpa"
},
{
"name": "loadbalance",
"parameters": "round_robin"
},
{
"name": "prometheus",
"parameters": "{$POD_IP}:9153"
},
{
"configBlock": "policy random",
"name": "forward",
"parameters": ". /etc/resolv.conf"
},
{
"name": "reload"
}],
"port": 5353,
"zones": [{
"zone": "."
}]
}],
"stub_domains": {
},
"tolerations": [{
"key": "node.kubernetes.io/not-ready",
"operator": "Exists",
"effect": "NoExecute",
"tolerationSeconds": 60
},
{
"key": "node.kubernetes.io/unreachable",
"operator": "Exists",
"effect": "NoExecute",
"tolerationSeconds": 60
}]
}
}
}
}