New TSM server

[influx]

I have a new AIX server that has 4 dual ported NICS, attached to 2 switches. The server will host 4 TSM instances. I would like to present all 8 ports as a single IP address and control the data via the TCPPORT. My network group is proposing 4 vlans and stating that I can NOT implement etherchannel/link aggegation due to the 4 vlan's.
The reason I want 1 IP address is for ease of administration, load balancing across all 4 TSM instances, simplicity of failover (1 FQDN/DNS change). I'm considering asking them to change to one vlan so I can implement etherchannel. Is this reasonable? What are others doing? What is best practice? Thanks.

 

[Mikey D]

Most etherchannel setups I've seen require the ports to all be on one switch, so that may need to be changed.

 

[javajockey]

We're doing something similar to this but with 2 1G ports. Basically the process is the same.
smit etherchannel to configure your network interface. Influx is right. Etherchannel normally assumes there is one switch. There is an option for a backup interface. If you go that route, make sure it is on a separate switch. I would recommend using 6 interfaces as the primary, and 2 as a backup. Be vary careful on what mode you use. Your network guys need to work with you to get the best performance.

 

[influx]

My network folks are warning against making one VLAN vs 4 VLANS. They've advised me that one big VLAN will cause too much broadcast traffic on the network and are concerned it will degrade throughput on my AIX server. Not sure of the validity of this statement/comment. Can anyone advise. Thanks.

 

[javajockey]

I'm not a network engineer, but that does not make any sense. Etherchannel assumes that you have multiple interfaces are "bound" to a single IP. I don't see how it is even possible to have the interfaces on separate VLANS. As for broadcast traffic, make sure you have both the switch and etherchannel settings using either 802.ad or native cisco etherchannel. Aslo make sure the hash modes match. I've been using etherchannel for a while now, so far it's been great.

 

[influx]

Javajockey,

Hmmm... maybe I should have restated the new issue. We have 4 fiberchannel ports on the server. The network folks are saying, create 4 VLANS and 4 distinct IP addresses. Initially I wanted 1 VLAN, and the 4 physical IP's "bonded" behind the one virtual. The network group advised that having one big VLAN could cause too much broadcast traffic on the network.

 

[influx]

Tommy, can you expound on that last statement, "In theory, the statement from your network group that having one big VLAN could cause too much broadcast traffic is the opposite of the theory.... " I'm not sure I understand.

 

[Mita201]

Influx,

Do you and your network guys speak common language? Do you understand each other well?
When you say "I want 4 eth ports from ONE computer (TSM server) agrregated (for bandwidth, failover, loadbalancing, whatever is your concern)" you are right.
When they said 4 VLANs are better than one big VLAN for less broadcast they are right too, but this is speaking about the network as whole, not about one computer with one IP address. So, you are both right, but not talking about same thing. It looks like you are talking about one host, and they are talking about whole network.

 

[syntax44]

Influx, I've removed my previous post as (after reading it again) it is partially wrong. The comment by Mita201 is wat I was trying to say as well.