SDA Transit - Move from legacy to LISP Pub/Sub

[ImrichPalascak]

Hi experts,

My client (city) is moving to SD-Access. We've been testing for roughly 6 monts the traditional deployement with IP Base transit and all the fast convergence tweaks (eem border restart, iBGP between the borders etc). Now we're close to deploy first site (in a month~) but I'm still considering to switch to LISP Pub/Sub to get rid of those tweaks and make my customer operation of the fabric easier. I've tried to test (in the lab with few devices) "move" from traditional IP Base to SDA LISP Pub/Sub and it's seems to be working but I want to make sure that the process is correct and smooth in real deployment we have now.

1. Remove IP Pools from VNs and Delete the VN's 
2. Remove devices from the fabric
3. Remove the legacy fabric site and legacy IP transit
4. Create new fabric site (zones optional)
5. Add Control Plane with Pub/Sub and make site to be configured with LISP Pub/Sub.
6. Crete SDA LISP Pub/Sub transit 
7. Add rest of the device into the fabric and finish the host onboarding

My questions is following: Are there any other dependencies I should consider when rebuilding the fabric from legacy to LISP Pub/Sub? Should anything else to be removed so we don't end up in NC*** Error messages? 

Many thanks in advance for any inputs.

Imrich

[jedolphi · Accepted solution]

Hi Imrich. I regularly convert my lab from LISP/BGP to LISP Pub/Sub. Make sure all fabric devices are running minimum of IOS XE 17.6 for Pub/Sub support. Step 3 and 4 are not necessary. Otherwise your proposal looks good. Jerome

[ImrichPalascak]

Many thanks Jerome for reply!

From the consulting point of view, is it safe to say that LISP Pub/Sub is the way to go for new deployements? I Have some in pipeline and I want to make sure I don't do LISP BGP PoC's anymore. 

[jedolphi · Accepted solution]

Hi Imrich, Pub/Sub is the long term strategy for SD-Access and I personally position Pub/Sub for new designs. Some highly conservative customers prefer to use what they know (LISP/BGP) with a view to migrate to Pub/Sub later. The tradeoff however is that they'll need to migrate later ☺ . Cheers, Jerome

[ImrichPalascak]

Spoiler

Pub/Sub is the long term strategy for SD-Access and I personally position Pub/Sub for new designs

That's what I needed from expert like you I'm not worried then anymore to position it for our projects. Many thanks once again Jerome.

Greetings to Cisco fellas!