Switching

Hello,

Hardware and software in question:

Juniper:

hardware: EX4300-48MP (multigigabit)

Junos ver: 18.3R1.9

Cisco:

Hardware: Catalyst 4300X-16 port in virtual stack (VSS) that consists of two units

Ios ver: 15.0(1r)SG10

Issue:

I've setup LAG 10g interfaces (4 ports) but when I enable ports on both sides, on juniper all ports are no longer accessible. Weird part(s):

- the management interface is inaccessible event though it shows in junos cli  "up" status. All 4 10g ports are also showing up status and indicator led on the hardware is showing active/green light.

- On Cisco side is the same story. All 4 ports are showing connected, including ether-channel and also, indicator led on the hardware is showing active/green light.

Relevant ports configuration on Juniper:

============================

xe-0/2/0 {
ether-options {
802.3ad ae1;
}
}
xe-0/2/1 {
ether-options {
802.3ad ae1;
}
}
xe-0/2/2 {
ether-options {
802.3ad ae1;
}
}
xe-0/2/3 {
ether-options {
802.3ad ae1;
}
}
ae1 {
description "LAG to Cisco";
aggregated-ether-options {
lacp {
active;

================================================

Relevant Cisco configuration:

================================================

interface Port-channel111
description HR SRV RM
switchport
switchport mode trunk

!

interface TenGigabitEthernet1/1/5
description HR Jun4300 Link 1
switchport mode trunk
channel-group 111 mode active
!
interface TenGigabitEthernet1/1/6
description HR Jun4300 Link 2
switchport mode trunk
channel-group 111 mode active

!

interface TenGigabitEthernet2/1/13
description HR Jun4300 Link 3
switchport mode trunk
channel-group 111 mode active
!
interface TenGigabitEthernet2/1/14
description HR Jun4300 Link 4
switchport mode trunk
channel-group 111 mode active

============================================================

Any suggestion would be greatly appreciated.

I think you have missed to define your ae1 interface as a switchport with tagged vlans - at least your configuration doesn't show.

Something like this to allow all vlans on the trunk:

set interfaces ae1.0 family ethernet-swithing interface-mode trunk

set interfaces ae1.0 family ethernet-swithing vlan members all

Let us know if this resolves your issue.

Hi Jonas and thank you for the reply.

It is defined but in my haste, I neglected to copy entire config for the interface:

=======================

ae1 {
description "LAG to Cisco";
aggregated-ether-options {
lacp {
active;
}
}
unit 0 {
family ethernet-switching {
interface-mode trunk;
vlan {
members [ default all ];
}

======================

Please note: Single link without aggregation, works fine and traffic flows between switches.

Regards,

T

I suspect that you definition of both vlan members default and all makes an error. I will suggest to remove vlan default:

delete interfaces ae1.0 family ethernet-switching vlan members defaults

If it still doesn't work, please provide the following output from the Juniper switch. You can obfuscate vlan names if needed.

show ethernet-switching interface ae1

show spanning-tree interface ae1

show ethernet-switching table interface ae1.0

I've attached the command output and sorry for formatting which is not that great.

Thank you!

T

Attachment(s)

config.pdf   56 KB 1 version

Everything looks OK as mac addresses are learned on the different vlans and STP is forwarding.

Another guess from here: is your management of the EX switch placed on the default vlan? If yes, then you need to define native-vlan on ae1 as Cisco per default sends vlan 1 untagged via trunk links and juniper puts a tag on everything.

Native vlan is configured like this:

set interfaces ae1 native-vlan-id 1

If this is a wrong guess, please test if you can configure a random access port with VLAN2 (vlan tag 20) and see if you can see the mac address of your test host on the Cisco switches. 'show mac-address table vlan 20 | i Po111' or similar - my Cisco-foo is very rusty 🙂

Spot on! defining native vlan1 on interface ae1 was the key!

I've been working with cisco gear for over 20 years and twice already I have tried to move to Juniper. I like everything about Juniper's hardware and cli.

Issue that I have with Juniper is not so good and knowledgable salespeople and support is kind of iffy - I've spent a few hours with Juniper's support looking into this issue and gave up as tech was a bit to inexperienced and I knew solution is as always, very simple  -  You sir, have proved that!</rant>

I don't know much about juniper equipment, especially this new line - it makes no sense to me why management interface would be affected by default vlan definition on ae1 link when different physical cables are used... Time to get some books.

I owe you a beer or two so if you are in Toronto area, let me know.

Regards,

T