When adding a routing interface to a VLAN or bridge domain within a logical system, users may encounter the "Error in parsing bridge domains/vlans" commit error message.

This article explains why and what must be done to resolve the issue.

When adding a routing interface to a VLAN/bridge domain within a logical system, the following error message is seen:

Jtac@Lab-Router# commit check
re0:
[edit logical-systems R2 bridge-domains]
  'v101'
    Error in parsing bridge domains/vlans:
error: configuration check-out failed

This might happen when the same IRB interface is used in two logical systems.

Junos OS cannot commit this configuration because one interface cannot be included in more than one logical system.

In our example, the irb.101 interface is already configured with another logical system.

logical-systems {
    R1 {
        bridge-domains {
            v101 {
                domain-type bridge;
                vlan-id 101;
                routing-interface irb.101;
            }
        }
    }
    R2 {
        bridge-domains {
            v101 {
                domain-type bridge;
                vlan-id 101;
            }
        }
    }
}

To resolve the error and commit any change of configuration, the IRB interface configuration must be changed.

logical-systems {
    R1 {
        bridge-domains {
            v101 {
                domain-type bridge;
                vlan-id 101;
                routing-interface irb.101;
            }
        }
    }
    R2 {
        bridge-domains {
            v101 {
                domain-type bridge;
                vlan-id 101;
                routing-interface irb.102;
            }
        }
    }
}

Note: The same logical interface cannot be associated with multiple domains or instances. If this is attempted, the same error can be expected.