RE: High Availability. (Maybe OT)

[Aamir Lakhani]

No problem, I have done this plenty of times. You have two switches connected together via a trunk port. On the server side, Intel makes duel port NIC cards that can be setup for failover or load balancing. In failover mode when a link dies dies on one port, the next port becomes active. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Kevin Welch Sent: Friday, October 13, 2000 3:08 AM To: [EMAIL PROTECTED] Subject: High Availability. (Maybe OT) I am trying to figure out how to impliment a redundant network design.  The problem I keep running into is the connection to the server.  I can provide Access redundancy through the use of two switches.  I can provide some level of server redundancy via the use of 2 NICs or 2 Servers.  The problem is how to provide application layer redundancy.  I have been able to prove the network itself is redundant, but connectivity to servers seems to be where I am having trouble with my studies.   From my understanding I cannot do etherchannel accross switches, and more over, I remember that etherchannel does not provide redundancy because if one link goes down the whole channel goes down.  Please correct me if this is wrong.    Example:   Realizing that the expectation that a server stay up all the time would still be a single point of failure.  In the event of a network failure on a switch, how do I provide network access to the Server.    Proposed is to connect the server via a second NIC or second port on a dual or quad NIC to a secondary access switch.    Problem, maintaing the same layer 3 address accross both switches in the advent that one link should fail, the server maintains reachability.   Giving that in this case I would be talking about a solaris system, I have thought about using simple scripts to watch for the interface to go down and reconfigure.  I am curious if anyone knows of any hardware/software solutions for doing this?   I am guessing that I am not the first person to ask for something like this.   -- Kevin