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troubleshooting LAG

[ Edited ]
‎05-26-2020 10:06 PM

Hi

I couldn't find the following same throobleshooting thing for the qfx product...any help?

Resolution Guide - EX - Troubleshoot Aggregated Ethernet Interface (LAG)

https://kb.juniper.net/InfoCenter/index?page=content&id=KB19798

 

And also is there a way on the qfx to check whether or not cross site LAG has one or two Physical interfaces?

 

qfx(2XPhysical Interfaces)----->ae5---------------------------------------->?Xremote interface----HPSwitch

9 REPLIES 9
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Re: troubleshooting LAG

‎05-26-2020 10:22 PM

Hi Arix,

 

There should not be much of a difference in troubleshooting LAG on EX and QFX devices. Are you seeing any command or step that does not work on QFX? If so, please let us know. We can find an alternate command for you that is specific to QFX.

 

The below document specific to QFX should help you with verification of LAG status :

https://www.juniper.net/documentation/en_US/junos/topics/task/verification/aggregated-ethernet-inter...

 

Hope this helps 🙂

 

Please mark "Accept as Solution" if this works for you.

Kudos are always appreciated!

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Re: troubleshooting LAG

‎05-26-2020 11:06 PM

Hello Arix,

There is no difference between Troubelshooting LAG in EX series or QFX series and you can apply same to verify the LAG connectivity .

 

https://kb.juniper.net/InfoCenter/index?page=content&id=KB19798

If you specifically looking for how the LAG is configured in QFX switch You can go for the below docs

 

https://www.juniper.net/documentation/en_US/junos/topics/topic-map/switches-interface-aggregated.htm...

 

 

Please mark "Accept as Solution" if this works for you.

Kudos are always appreciated!

deeksha
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Re: troubleshooting LAG

‎05-27-2020 12:25 AM

thanks for responses...

 

How about my second question?

And also is there a way on the qfx to check whether or not unmanaged cross site's LAG has one or two Physical interfaces?

qfx(2XPhysical Interfaces)----->ae5----------------Network---------------------->?Xremote interface----HPSwitch

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Re: troubleshooting LAG

[ Edited ]
‎05-27-2020 12:49 AM

Hi Arix,

 

If I am getting your question correctly, you want to check how many interfaces are configured under LAG on the peer end device. Correct?

 

Firstly, a LAG needs to have a minimum number of links up in order for it to function correctly. Considering your LAG on one end had 2 interfaces configured. You will need 2 other interfaces on the other end. Only then it forms 2 links ( child interfaces) on each end. Ideally, in a simple LAG, both the devices will have the same number of interfaces. 

 

For the LAG to operate correctly, it is necessary to coordinate the two end systems connected by the LAG, either manually or automatically.

 

Please refer:

https://www.juniper.net/documentation/en_US/junos/topics/topic-map/switches-interface-aggregated.htm...

 

From the same guide, you are referring to, I am pasting the below:

root@KE-1-4200# run show interfaces terse | match ae0     
ge-0/0/5.0       up    up   aenet    --> ae0.0   <<<<< LAG Child Interface
ge-0/0/6.0       up    up   aenet    --> ae0.0   <<<<< LAG Child Interface
ae0              up    up                  <<<<< LAG Parent Interface
ae0.0            up    up   eth-switch     <<<<< LAG Logical Interface

 You can verify what interfaces are a part of your local device by running the above command. For ae0 aggregated interface, ge-0/0/5.0 and ge-0/0/6.0 are child interfaces. 

 

To find child interfaces that are part of a LAG bundle: ( you can check the show interfaces extensive output )

Logical interface ae142.0 

<snip>
Link:
et-2/0/0.0
Input : xxxx
Output: xxxx
et-2/0/1.0
Input : 7xxxx
Output: xxxx

To find parent LAG interface that a child interface is a part of:

Logical interface et-2/0/0.0

<snip>
Protocol aenet, AE bundle: ae142.0, xxxxx

 

Hope this helps 🙂

 

Please mark this post as "Accepted Solution" so that it can help others too.

Kudos are always appreciated.

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Re: troubleshooting LAG

‎05-27-2020 02:16 AM

Many thanks for replies..

Let me clear my question:

What can be seeing on my local interface of ae14 (2XChild Physical IF attached) when the one of the 2 interfaces on the other end(My Peer) device (HP switch and we can not managed) is fails?

Topology:

Qfx[2xPhysical Int attached to ae14]============3rtPary F/O Carrier==========MyPeer's HP switch[2xPhyIF attached theirLAG]

Both end interfaces are 10G

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Re: troubleshooting LAG

‎05-27-2020 02:29 AM

Hi Arix,

 

The ae interface will show "down". By default, the minimum links (child interfaces) that are supposed to be up for an ae interface to remain up is 1. This is changeable. Considering your device is running on default behavior, if the other end child interfaces show "down", then the aggregate interface also shows down. And the Child Interface will show "Detached" in its MUX State for LACP protocol output.

 

If you have 2 child interfaces in your ae bundle and one interface goes down and your minimum links are running as per default value(1), then your ae bundle will still remain up but the link will show down.

 

Example: (Here, only ge-0/0/6 is LACP down and ge-0/0/5 is up  )

root@KE-1-4200# run show lacp interfaces    
Aggregated interface: ae0
    LACP state:       Role   Exp   Def  Dist  Col  Syn  Aggr  Timeout  Activity
      ge-0/0/5       Actor    No    No   Yes  Yes  Yes   Yes     Fast    Active
      ge-0/0/5     Partner    No    No   Yes  Yes  Yes   Yes     Slow   Passive
      ge-0/0/6       Actor    No   Yes    No   No   No   Yes     Fast    Active
      ge-0/0/6     Partner    No   Yes    No   No   No   Yes     Fast   Passive
    LACP protocol:        Receive State  Transmit State          Mux State 
      ge-0/0/5                  Current   Slow periodic    Collecting distributing
      ge-0/0/6            Port disabled     No periodic           Detached

  

Let me know if you have more queries. 

 

Please mark "Accepted Solution" if this helps you solve your queries.

Kudos are always appreciated.

 

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Re: troubleshooting LAG

[ Edited ]
‎05-27-2020 06:26 AM

Thanks replies..

 

Another qs:

LAG has a single child interface...To create redundancy, it is needed to add a new physical child interface into existing LAg in production, In this case existing traffic will be impacted or no? 

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Re: troubleshooting LAG

‎05-27-2020 06:31 AM

Hi Arix

 

Adding a lag member on the fly should not cause any problem however it would not be a recommendation.

 

 

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Re: troubleshooting LAG

‎05-27-2020 06:33 AM

Hi Arix,

 

Please mark "Accepted Solution" for posts that solve your query so that it helps others as well.

Kudos are always appreciated! 

 

For Junos OS, when a new interface is added as a member to the aggregated Ethernet bundle, a link flap event is generated. When you add an interface to the bundle, the physical interface is deleted as of a regular interface and then added back as a member. During this time, the details of the physical interface are lost.

 

Please refer the below:

https://www.juniper.net/documentation/en_US/junos/topics/topic-map/switches-interface-aggregated.htm...

 

Hope this helps 🙂

 

 

 

 

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