Deployment Strategies

Blue -Green or Red- Black Deployment:

lets say we have 3 instance of version v1 and i want to update the version 1 to v2 then i have to create 3 instance of v2 and slowing i have to pass the traffic to the V2 then at certain point all the traffic goes to the V2 if any issues get then we can roll back the traffic to v1 with 100%

Drawback is we have to create same number of instance

Rolling Update:

so we have to update the instance to V2 then we don’t need to create seperate instance just we update the v1 to V2 if any case we can roll back to V2 but here there is no pause we can’t monitor

Canary :

Here lets say we have 3 instance of v1 so we do only one instance update to v2 then we send 1% of the traffic to that so we can monitor and we cause pause also and we have more control over traffic later we can slowly increase the traffic and update the instance and also, we can b=rollback

it uses capabilities of Both Blue green and roll update