CoreDNS - Container Service for Kubernetes - Alibaba Cloud Documentation Center

CoreDNS is the default DNS service discovery plug-in for ACK and ACK Edge clusters. You can also use the CoreDNS component for service discovery in ACK Serverless clusters. This topic describes the CoreDNS component, explains how to use it, and provides its change log.

Component introduction

CoreDNS is the component in Kubernetes clusters that handles DNS resolution. It resolves both internal custom service domain names and external domain names. The CoreDNS project is hosted by the Cloud Native Computing Foundation (CNCF). For more information about CoreDNS, see CoreDNS: DNS and Service Discovery.

CoreDNS has two editions: unmanaged and managed. For more information, see DNS for service discovery.

For more information about the mappings between CoreDNS versions and cluster versions, see CoreDNS version in Kubernetes.

Notes

The DNS configurations in application pods also affect DNS resolution results. For more information, see Configure DNS policies and domain name resolution.
Before you upgrade an unmanaged CoreDNS component, note the following:
- Read the instructions for upgrading CoreDNS. For more information, see Automatically upgrade an unmanaged CoreDNS component.
- Back up the coredns ConfigMap in the kube-system namespace.
An unavailable CoreDNS service can severely affect other services in the cluster.
- Unmanaged CoreDNS: You are responsible for ensuring the availability of CoreDNS. For more information, see Suggestions for deploying a stable and high-performance unmanaged CoreDNS component.
- Managed CoreDNS: ACK ensures the availability. For more information, see Performance of managed CoreDNS.

Change log

Unmanaged edition

Version number	Applicable clusters	Image URL	Change date	Changes	Impact
v1.12.1.3	For clusters of v1.27 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.12.1.3	November 5, 2025	Optimization: Added matchLabelKeys to `topologySpreadConstraints` to prevent CoreDNS pods from being concentrated in a single zone after a rolling upgrade, which is not the expected behavior. For more information, see Use scheduling policies to achieve high availability for CoreDNS.	This upgrade does not affect your services.
v1.12.1.2	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.12.1.2	October 10, 2025	Optimization: Removed the `aliyun` suffix from the component version number. The default configuration of `cache` for the `serve_stale` plug-in is optimized to `serve_stale 30s verify`.	This upgrade does not affect your services.
v1.12.1.1-4035d7a99-aliyun	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.12.1.1-4035d7a99-aliyun	July 22, 2025	Upgraded to the community edition v1.12.1. Added the multisocket plug-in. Increased the CNAME lookup limit from 7 to 10. plugin/kubernetes: Fixed an issue where DNS queries were resolved to deleted pods due to DeletionTimestamp (#7119) (#7131). plugin/kubernetes: Reverted the change "Only create PTR records for endpoints with a defined hostname (#6898)". plugin/forward: Added the `failfast_all_unhealthy_upstreams` option. This option returns `servfail` when all upstream servers are down. The `cache` plug-in enables the `serve_stale` configuration by default. When an upstream DNS server is unavailable, CoreDNS can use an expired cache to provide an acknowledgement (the TTL of this acknowledgement is 0) and asynchronously tries to obtain the latest address of the domain name.	This upgrade does not affect your services.
v1.11.3.5-5321daf49-aliyun	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.11.3.5-5321daf49-aliyun	March 19, 2025	Updated the base image to fix related security vulnerabilities. Added support for Node Lingjun pools. CoreDNS pods are not scheduled to Node Lingjun.	This upgrade does not affect your services.
v1.11.3.2-f57ea7ed6-aliyun	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.11.3.2-f57ea7ed6-aliyun	October 21, 2024	CoreDNS now supports the Firewall plug-in. The Forward plug-in can execute the next plug-in based on the return code. You can customize the topology constraint options for CoreDNS component deployments on the Operations Management > Component Management page of the console.	This upgrade does not affect your services.
v1.9.3.16-4341f22f-aliyun	For ACK Serverless clusters of v1.20.4 and later only.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.16-4341f22f-aliyun	May 9, 2023	The default memory request for scheduling CoreDNS containers is increased to 4 GiB to prevent CoreDNS from being scheduled to shared instances. You can customize the memory size in the component configuration.	The upgrade may result in the use of higher ECI specifications when you create CoreDNS.
v1.9.3.10-7dfca203-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.10-7dfca203-aliyun	April 3, 2023	Optimized zone-level anti-affinity scheduling. Reduced the possibility of pod eviction in elastic node scenarios.	Due to scheduling policy adjustments, if all schedulable nodes in the cluster are in a single zone, CoreDNS replicas may fail to be scheduled and the component upgrade may fail. To ensure DNS availability, scale out your cluster and distribute the schedulable nodes across multiple zones. This ensures that CoreDNS replicas can be scheduled and run.
v1.9.3.6-32932850-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.6-32932850-aliyun	August 25, 2022	Supports the delivery of Kubernetes events. In ACK Serverless clusters, the default CPU request is changed to 2 cores.	This upgrade does not affect your services.
v1.9.3.2-8850b5e7-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.2-8850b5e7-aliyun	August 3, 2022	You can enable the CoreDNS log collection feature in Log Service with a single click.	This upgrade does not affect your services.
v1.9.3.1-5e7ba42d-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.1-5e7ba42d-aliyun	July 11, 2022	Fixed several issues and added some features. For more information, see CoreDNS-1.9.3 Release. Supports ACK One multi-cluster services.	This upgrade does not affect your services.
v1.8.4.5-2ce07fd2-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.8.4.5-2ce07fd2-aliyun	April 8, 2022	Optimized the CoreDNS scheduling affinity configuration to allow all cluster nodes to be elastic scaling nodes.	This upgrade does not affect your services.
v1.8.4.3-644f4735-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.8.4.3-644f4735-aliyun	February 22, 2022	Disabled caching for resolution results of the ServError type. Changed anti-affinity scheduling by hostname from `preferred` to `required`. This enforces anti-affinity scheduling by node.	Because replica anti-affinity is enforced by node, some CoreDNS replicas will be in the Pending state if the number of CoreDNS replicas is greater than the number of nodes. Before you upgrade to this version, scale out the cluster nodes or scale in the CoreDNS replicas.
v1.8.4.2-7d597cff-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.8.4.2-3a376cc-aliyun	January 10, 2022	Added support for custom parameters. Enabled resolution logs by default.	This upgrade does not affect your services.
v1.8.4.1-3a376cc-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.8.4.1-3a376cc-aliyun	October 26, 2021	Supports listeners for EndpointSlices resources. Supports DNS queries using IPv6 addresses.	This upgrade does not affect your services.
v1.7.0.0-f59c03d-aliyun	For clusters of v1.14.8 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.7.0.0-f59c03d-aliyun	July 8, 2021	Modified the default graceful shutdown time for CoreDNS and the container memory limit in the CoreDNS deployment. Updated metric names. If your monitoring system depends on CoreDNS metrics, make the necessary changes. For more information, see Metric Changes. Fixed an issue where the Forward plug-in used only the first upstream DNS server. Removed compatibility for the deprecated Upstream plug-in. If your Corefile configuration contains the Upstream plug-in, it is safely and automatically deleted during the upgrade.	If you previously modified the /etc/resolv.conf DNS configuration file on an ECS instance, upgrading or recreating a CoreDNS pod causes it to use the modified /etc/resolv.conf file. Before you upgrade, make sure that all DNS servers in the configuration are working correctly.
1.6.7.edge (Discontinued)	-	registry.{{.Region}}.aliyuncs.com/acs/coredns:1.6.7.edge	April 23, 2021	Built based on the community edition 1.6.7. For more information, see CoreDNS-1.6.7 Release.	This upgrade does not affect your services.
v1.7.0	-	registry.{{.Region}}.aliyuncs.com/acs/coredns:1.7.0	March 18, 2021	Removed compatibility for the deprecated Upstream plug-in. If your Corefile configuration contains the Upstream plug-in, it is safely and automatically deleted during the upgrade. Updated metric names. If your monitoring system depends on CoreDNS metrics, make the necessary changes. For more information, see Metric Changes. Fixed an issue where the Forward plug-in used only the first upstream DNS server.	If you previously modified the /etc/resolv.conf DNS configuration file on an ECS instance, upgrading or recreating a CoreDNS pod causes it to use the modified /etc/resolv.conf file. Before you upgrade, make sure that all DNS servers in the configuration are working correctly.
v1.6.7 (Discontinued)	-	registry.{{.Region}}.aliyuncs.com/acs/coredns:1.6.7	November 28, 2018	Built based on the community edition 1.6.7. For more information, see CoreDNS-1.6.7 Release.	This upgrade does not affect your services.

Managed edition

Version number	Applicable clusters	Image URL	Change date	Changes	Impact
v1.12.1.2	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.12.1.2	October 10, 2025	Optimization: Upgraded to the community edition v1.12.1. In clusters where the IPv6 dual-stack feature is not enabled, queries for AAAA records directly return `nodata`. By default, the multisocket plug-in is enabled to enhance performance.	This upgrade does not affect your services.
v1.11.3.2-f57ea7ed6-aliyun	For clusters of v1.21 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.11.3.2-f57ea7ed6-aliyun	October 21, 2024	CoreDNS now supports the Firewall plug-in. The Forward plug-in can execute the next plug-in based on the return code. You can customize the topology constraint options for CoreDNS component deployments on the Operations Management > Component Management page of the console.	This upgrade does not affect your services.
v1.9.3.10-7dfca203-aliyun	For clusters of v1.20.4 and later.	registry.{{.Region}}.aliyuncs.com/acs/coredns:v1.9.3.10-7dfca203-aliyun	April 3, 2023	Optimized zone-level anti-affinity scheduling. Reduced the possibility of pod eviction in elastic node scenarios.	Due to scheduling policy adjustments, if all schedulable nodes in the cluster are in a single zone, CoreDNS replicas may fail to be scheduled and the component upgrade may fail. To ensure DNS availability, scale out your cluster and distribute the schedulable nodes across multiple zones. This ensures that CoreDNS replicas can be scheduled and run.