To complete the network configuration for the new codfw switches in row's C and D we need to migrate the uplinks from the current //asw-c-codfw// and //asw-d-codfw// virtual-chassis so they terminate on the new Spine swithces in row D instead of directly on the core routers.
This is quite a delicate change but should be possible without causing any interruption to service. It may make sense to do a dns depool of the site in advance as a precaution and to reduce traffic levels (as at many points we will be on 1 leg rather than 2). Steps are roughly as follows:
# Create ESI-LAG ae0 on both spine switches, with single member port, et-0/0/28, on each (for asw-c)
# Create ESI-LAG ae1 on both spine switches, with single member port, et-0/0/27, on each (for asw-d)
# Add the current set of vlans in use on asw-c-codfw and asw-d-codfw to //ssw1-d1-codfw// and //ssw1-d8-codfw//
# Trunk those vlans over //ssw1-d8-codfw// port et-0/0/31towards cr2-codfw
# Trunk the row C vlans over ae0 on the spines
# Trunk the row D vlans over ae1 on the spines
# Change the VRRP priority on //cr2-codfw// so that it is VRRP master for the row C vlans
# Disable interfaces et-1/1/0 and ae3 on //cr1-codfw// (ports facing //asw-c-codfw//)
## Inbound and outbound traffic to row C still flows from //cr2-codfw// et-1/1/0 to //asw-c7-codfw// et-7/0/52
# Re-cable //asw-c2-codfw// et-2/0/51 to //ssw1-d1-codfw// et-0/0/28
# Check row C MAC addresses are learnt on ssw1-d1-codfw ae0 and known on ssw1-d8-codfw via evpn
# Change the VRRP priority on //cr2-codfw// so that it is VRRP master for the row D vlans
# Disable interfaces et-1/1/3 and ae4 on //cr1-codfw// (ports facing //asw-d-codfw//)
## Inbound and outbound traffic to row D still flows from //cr2-codfw// et-1/1/3 to //asw-c7-codfw// et-7/0/52
# Re-cable //asw-d2-codfw// et-2/0/51 to //ssw1-d1-codfw// et-0/0/27
# Check row D MAC addresses are learnt on ssw1-d1-codfw ae1 and known on //ssw1-d8-codfw//via evpn
# Drain transport circuits to //cr3-eqsin// and //cr1-eqiad// on //cr1-codfw//
# Deactivate Arelion transit on //cr1-codfw// xe-1/0/1:0
# Reconfigure PIC 1/0 on //cr1-codfw//
## Delete the 40G configuration for ports 0 and 3
## Add a 100G configuration for port 2
# Reset PIC 1/0 on cr1-codfw
# Un-drain transport circuits to //cr3-eqsin// and //cr1-eqiad// on //cr1-codfw//
# Re-activate Arelion transit on //cr1-codfw// xe-1/0/1:0
# Enable //cr1-codfw// et-1/0/2 in Netbox (connects to ssw1-d1-codfw) and push with Homer
# Move the //cr1-codfw// ae3 and ae4 vlan sub-interfaces to et-1/0/2
# Add the new sub-ints of et-1/0/2 as OSPF stub interfaces, remove the old ae3/ae4 sub-ints from OSPF
# Check on cr2-codfw that it now sees cr1-codfw as VRRP backup for all vlans again
## L2 path here is from cr2-codfw -> asw -> ssw -> cr1-codfw
# Reconfigure the cr1-codfw new sub-interfaces so it they are VRRP masters for row C vlans
# Disable //cr2-codfw// et-1/1/0 and ae3 (ports facing //asw-c-codfw//)
# Move //cr2-codfw// ae3 sub-interface configs to et-1/0/2 (port facing //ssw1-d8-codfw//)
# Check on //cr1-codfw// that it sees //cr2-codfw// as VRRP backup for row C vlans again
## L2 path here is from cr1-codfw -> ssw1-d1 -> ssw1-d8 -> cr2-codfw
# Re-cable //asw-c7-codfw// et-7/0/52 to //ssw1-d8-codfw// et-0/0/28 (had been going to cr2)
# Reconfigure //asw-c-codfw// et-7/0/52 so it is part of ae1, and delete ae2 config
# Check ESI-LAG on et-0/0/28 of both spines is working and ae1 up on spines and asw-c-codfw
# Reconfigure the cr1-codfw new sub-interfaces so they are VRRP masters for row D vlans
# Disable //cr2-codfw// et-1/1/3 and ae4 (ports facing //asw-d-codfw//)
# Move //cr2-codfw// ae4 sub-interface configs to et-1/0/2 (port facing //ssw1-d8-codfw//)
# Check on //cr1-codfw// that it sees //cr2-codfw// as VRRP backup for row D vlans again
## L2 path here is from cr1-codfw -> ssw1-d1 -> ssw1-d8 -> cr2-codfw
# Re-cable //asw-d7-codfw// et-7/0/52 to //ssw1-d8-codfw// et-0/0/27 (had been going to cr2)
# Reconfigure //asw-d-codfw// et-7/0/52 so it is part of ae1, and delete ae2 config
# Check ESI-LAG on et-0/0/27 of both spines is working and ae2 up (spines) and ae1 up (//asw-d-codfw//)
# Re-balance VRRP settings on both CRs as they had been prior to start