Compatibility Risks

Check Items

Read the version compatibility differences and ensure that they are not affected. The patch upgrade does not involve version compatibility differences.

Version compatibility

Upgrade Path	Version Difference	Self-Check
v1.23 or v1.25 Upgraded to v1.27	Docker is no longer recommended. Use containerd instead. For details, see Container Engine.	This item has been included in the pre-upgrade check.

Upgrade Path

Version Difference

Self-Check

v1.23 or v1.25

Upgraded to v1.27

Docker is no longer recommended. Use containerd instead. For details, see Container Engine.

This item has been included in the pre-upgrade check.

**Table 1** QoS class changes before and after the upgrade
Init Container (Calculated Based on spec.initContainers)	Service Container (Calculated Based on spec.containers)	Pod (Calculated Based on spec.containers and spec.initContainers)	Impacted or Not
Guaranteed	Besteffort	Burstable	Yes
Guaranteed	Burstable	Burstable	No
Guaranteed	Guaranteed	Guaranteed	No
Besteffort	Besteffort	Besteffort	No
Besteffort	Burstable	Burstable	No
Besteffort	Guaranteed	Burstable	Yes
Burstable	Besteffort	Burstable	Yes
Burstable	Burstable	Burstable	No
Burstable	Guaranteed	Burstable	Yes