VMs with security groups allowing all egress traffic cannot access the Internet in 4.23.0.0

[weizhouapache]

problem

Description

In CloudStack 4.23.0.0, a VM cannot access the Internet when its security group has egress rules configured, even when the egress rules allow all outbound traffic (0.0.0.0/0).

The same configuration works as expected in older CloudStack versions.

The issue occurs when the security group has egress rules but no ingress rules.

Expected behavior

The VM should be able to initiate outbound connections to the Internet when the security group has an egress rule allowing all traffic.

According to the CloudStack documentation:

If there is no Egress rule in a Security Group, all the outgoing traffic will be allowed.
If there are Egress rules in a Security Group, only the outgoing traffic which match a Egress rule will be allowed.
Only the incoming traffic which match a Ingress rule will be allowed.

Actual behavior

With CloudStack 4.23.0.0:

• The VM has a security group assigned.
• The security group has one egress rule allowing ALL outbound traffic.
• There are no ingress rules.
• The VM cannot access the Internet.

versions

The versions of ACS, hypervisors, storage, network etc..

The steps to reproduce the bug

...

What to do about it?

No response