l2-dci-with-mlag-over-vpls-transport.html

---
date: 2011-02-24T16:48:00.000+01:00
tags:
- link aggregation
- VPN
- switching
- data center
- workshop
title: L2 DCI with MLAG over VPLS transport?
url: /2011/02/l2-dci-with-mlag-over-vpls-transport/
---

<p>One of the answers I got to my “<a href="/2011/02/how-would-you-use-vpls-transport-in-l2/">How would you use VPLS transport in L2 DCI</a>” question was also “Can’t you just order two VPLS services, use them as P2P links and bundle the two links into a multi-chassis link aggregation group (MLAG)?” like this:</p>
<figure><img src="/2011/02/s1600-VPLS_MLAG.png"></figure>
<!--more--><p>Unfortunately, the VPLS service is never totally transparent. While you might get STP running across VPLS (but probably only if you ask), I would be extremely surprised if the CE-switches could exchange LACP/PAgP packets; these packets would be usually intercepted by the first switch in the carrier’s network.</p>
<p>Still, you can configure static port channel on the CE-switches and get MLAG across VPLS to work ... assuming, of course, that you’re willing to trust the Service Provider to bring down the PE-CE interface if something breaks anywhere within the VPLS cloud (otherwise your static port channel will turn into a nice partial black hole).</p>
<p>You could also try to run your own end-to-end tests. This is where my guesswork starts; I would appreciate comments from experts more familiar with switching platforms. </p>
<p>UDLD is probably out of question (yet again, one would expect UDLD packets to be received by the first provider switch), but Ethernet OAM might fit the bill. My question would thus be: can we run end-to-end Ethernet OAM on an interface that is part of a static port channel? Has anyone got that working?</p>
<h4>More information</h4><p>Numerous L2 and L3 DCI scenarios are described in the <a href="https://www.ipspace.net/DCI">Data Center Interconnect</a> webinar. If you’d like to know more about the benefits and drawbacks of various VPN solutions (including pseudowires, VPLS, MPLS/VPN, IPsec-based VPNs and DMVPN), check out the <a href="https://www.ipspace.net/ChooseVPN">Choose the Optimal VPN Service</a> webinar.</p>
<p>Both webinars are also available as part of the <a href="https://www.ipspace.net/Subscription">yearly subscription package</a>.</p>