Switching

From KB17419:

 

The EX will tag and transmit the MGMT packets. To send untagged packets on the native vlan, the MGMT vlan has to be removed as a member of the trunk but left in the native vlan set to the MGMT.


Here's how it works:

MGMT is NOT a member of trunk, but it is a member of native VLAN:
Transmit = untagged (pass)
Receive = untagged (pass - mapped to MGMT)
Receive = tagged to MGMT (drop)

MGMT IS a member of trunk and native vlan:
Transmit = tagged (pass)
Receive = untagged (pass - mapped to MGMT)
Receive = tagged (pass)


So if a tagged VLAN needs to be send as untagged traffic, it should be configured only with the native-vlan id, and the VLAN should not be added under the port mode trunk configuration.

 

 

So the only way to get the native VLAN to be sent out untagged is to not allow it as a vlan member????  That means we can't use the "vlan members all" command, and instead have to explicity list every vlan possible, *except* the native vlan????  Please tell me I'm wrong.

 

Is there an easy/straight-forward way to do this?  Maybe something like "vlan members all-except-native"?

 

We have a large number of existing Cisco switches with a decent number of vlans that we need to connect to, and need to mimic their native vlan behavior (transmit *and* receive the native vlan untagged, and tag all other vlans). 

 

The Juniper method seems to require a huge amount of work (especially if you need to add a new vlan).  Am I the only one shocked at this behavior??

I found a potential solution here.  Has anyone tried this?

 

groups { 
PORT { 
vlans { 
<*> { 
interface { 
ge-2/0/15.0; 
} 
} 
} 
} 
} 

vlans { 
apply-groups PORT; 
vlan2 { 
vlan-id 2; 
apply-groups-except PORT; 
} 
[...] 
} 

 

Nobody else is surprised by this behavior? 

I might be 4 years late, but yes, I 'm surprised.

 

It almost cost me a customer some months ago, I was lucky to have found what the cause of my native vlan not working was in time.

 

Plus,  I have found no other solutions, except the one you posted and the obvious one (listing the vlans one by one)

This inspired me to try this:

 

# show interfaces ge-0/0/0

ge-0/0/0 {
    unit 0 {
        family ethernet-switching {
            port-mode trunk;
            vlan {
                members all;
                except NATIVE_VLAN_NAME;
            }
            native-vlan-id NATIVE_VLAN_NAME;
        }
    }
}

you have to use the name, not the vlan-id.

I cannot find it documented anywhere,  but it works for me (EX2200-C-12P, Junos 12.1R3.5 , 12.3R12.4 and some 14-version).

 

Hope this helps!

Thank you Erdem,
i have the same problem and found your solution. Indeed it seem that "except" is a hide command available only on some device/firmware. 
Lyckly i can use it on a ex4550 with 12.3R12.4. While is not available on a QFX5110 with 18.4R2-S8.

Hope that it will be integraded as a standaed command.

Regards,

------------------------------
CHRISTIAN BRASOLIN
------------------------------

Original Message:
Sent: 11-23-2016 12:30
From: Erdem Sener
Subject: Trunks, Vlan members all - and Native Vlan ID

This inspired me to try this:

 

# show interfaces ge-0/0/0ge-0/0/0 {    unit 0 {        family ethernet-switching {            port-mode trunk;            vlan {                members all;                except NATIVE_VLAN_NAME;            }            native-vlan-id NATIVE_VLAN_NAME;        }    }}

you have to use the name, not the vlan-id.

I cannot find it documented anywhere,  but it works for me (EX2200-C-12P, Junos 12.1R3.5 , 12.3R12.4 and some 14-version).

 

Hope this helps!