the sticky method (advanced) creates a sticky table, each entry containing client-ip/server-ip. When a server goes down, the entry is removed and a new one created.
The standard method does not use a sticky table but a hash algorithm. The algorithm takes the client ip and returns the index of a server.
The same client ip returns always the same index.
If a server goes down, the algorithm select the next available index.
This is where is the difference.
Assume the hash algorithm returns index of server-A. While A is alive, everything is fine. When A goes down, traffic will be sent to the next index, let's say B.
When A comes back alive, traffic is again sent to A.
With the advanced method, since a new entry pointing to B is created when A is down, when A comes back up, traffic is still sent to B.
Another difference is if you add or remove servers from the list. The hash algorithm may return different index.
Gilles.
