Migration from Oracle OTD to F5

i migrated around 70 LB services from F5 to other LB brand but i think you can use same high level method, i.e.:

a. migration was done in stages. migrating all at once is possible but very unfeasible and very high risk.

b. in each stages, around 20 services that share same VIPs were migrated.
it was feasible amount for 1 person.

c. new F5 LB needs client side self and floating IP addresses that should be in same subnet as the VIPs.
so assign unused IP from the those subnets to F5 before cutover.

d. make sure the firewall etc. are configured properly for new client side's and server side's self and floating IP addresses used by new F5 LB.
this includes ensuring backend servers allow traffic from new LB's server side IP address.

e. before the cut over, configuration was done in the new LB using dummy VIP, so they dont cause IP conflict with existing LB.

f. during cutover, simply change the migrated VIPs of old LB to dummy addresses then change dummy VIPs of new F5 LB to real VIPs. this step will be the downtime.

for the dummy VIP addreses, simpy use IP addresses that won't be routable to the LBs.
in my case, the LBs were behind NAT and the real VIPs are private addresses,
so i used eye catching public ip addresses, such as 111.111.111.111, etc. in order for people to easily see them as dummies.