UCS migration to ACI

[Jelena Mitrovic]

Hello,

We are having question regarding UCS system migration to ACI fabric. Consider next deployment where we are having one UCS system that is connected to the traditional network infrastructure with some VLAN i.e. VLAN 10. ACI fabric with the same VLAN 10 is deployed and we would like to in the migration phase move some of the UCS servers to the ACI fabric to perform some staging, after which all servers would be migrated to ACI fabric. Is it possible to connect some of UCS servers to the ACI fabric (static pinning) with the same VLAN 10 that is used for connection to traditional network that is currently configured as disjoined L2 network?

Please see picture in attach.

Regards,

Jelena

[sathish.munuswamy]

Hi Jelena, 

were you able to get direction on your migration strategy. We are currently at the same point. We have the VLANs pinned to a specific uplink port channel in UCS and planning to create another uplink port channel for the connection to ACI fabric, wondering if we need to create separate set of VLAN instances with the same ID and pin them to the new service profile instances?

Thanks

[Jelena Mitrovic]

Hi Sathish,

We have not yet implemented this migration so what I will write is just plan how we think this might work. For more assistance I suggest you contact your Cisco support.

We were planing to create a VLAN group with VLANs from VLAN range that's not used on existed legacy network, create additional pair of vNIC for servers by changing service-profile in UCS Manager, assign newly created vNICs to vDS in vCenter management interface and hard pin the VLAN group to Uplinks directed to ACI fabric in UCS Manager.

Hope this helps!

[sathish.munuswamy]

Thanks, we have the same plan and already working on adding NICs and creating additional uplinks from UCS. The tricky part is going to be entertaining VLANs that are currently managed by vmware standard switch. We have vmware management and vmotion traffic network in standard switch. We had a ticket open with TAC and was suggested to static bind those VLANs in a separate EPG. We are curious to see how this works out as well.

[joeharb]

We are starting the same deployment/migration, could you please let me know how your went and any addition information that either of you discovered.

Joe

[sathish.munuswamy]

Hi, 

We just completed our project and the migration went well, I am not able to speak much about the networking lessons learned, but with respect to UCS we utilized this opportunity to migrate workloads to UCS central with the same project. One man feature which helped us a lot is UCS VLAN groups. So ideally we did not use the same vlan ids on majority of cases. Created vlan group with pool of unused vlan ids and made sure the same vlan pool is reserved on aci side

Secondly in ucs profile we created dedicated set of vnics which are aci vnics and has the vlan groups reserved for aci. So when the migration comes pin the aci vlan group to the uplinks / portchannel connected to aci fabric and when you create the vmm and epfg association the new portgroup that gets created would pick one of vlan id that was already reserved and available in the ucs vlan group. This way the vlan id matches between ucs vnic and the portgroup in vmware and we just flipped the port groups during migration. For online migration we used L2 extension between aci and the traditional network stack. 

for static vlans it was tricky we just have to unpin and repin the vlan in ucs from traditional uplink to aci uplink and that will repin the vnic to the appropriate uplink in ucs. Hope this helps