LAN setup question

We have a ton of network congestion between our front and back office buildings, can you run dual fiber or will that create loops?

Also, for switch connectivity, do you dasiy chain or use a master switch config? Does going fiber between switches give you that much of an advantage over gig to gig?

A few answers and then some questions:

1: Yes you can run dual, triple, etc... fiber. You need to create a port channel which will act as one link between the switches. Otherwise the multiple links will be viewed as a loop and spanning tree (assuming you're using it) will block a port and you'll be back to square one.

2: As for switch connectivity, its almost always best to have a core switch and then run fiber out to each stack. (you could go to each switch but it couldbe cost prohibitive) Daisy chaining from one closet to another to another has the obvious disadvantage of one bad gbic or fiber taking out big sections of your network. Also local congestion could slow down your entire network.

3: Gig fiber and gig copper both run at the same speed. Fiber in new installations because of future growth, but if you've got copper already you don't need to upgrade for performance.

Now the big question:

Are you sure lack of bandwidth is the cause of your congestion? Have you monitored the connecting ports and seen high utilization rates?

Yeah we've monitored the ports. Some jackass might copy a gig worth of my document files to his home directory and completly shut down the entire network over the fiber. We only have 5 switches up front, they are all connected via gig to a master switch and the master switch has fiber run from the front office to the back office(where the servers are).

Our problems are mainly due to psts that sit on the file server those all those people up front have a constant connection with those.

We run HP switches, which I know are not the best, but they are definatly cost effective. I didn't know if running fiber from the other switches to the master switch would be any difference than running gig eth to the master switch.

Just to add to #3, fiber has other advantages/disadvantages wrt copper.

Advantages: Ability to go longer distances. No emanations come from fiber, which can be useful in some security settings. Ability to go 10gE, though Cu is coming.

Disadvantages: cost, fragility.

As Big_slacker said, speed has nothing to do with it.

"Our problems are mainly due to psts that sit on the file server those all those people up front have a constant connection with those."

The exchange server? PST's? Like they just keep old ones on there to access at a later time?

Damn fucking people and 2gig mail files.

Depends. Straight desktop users have their mail going straight to a PST to keep the exchange store down, while our laptop users are live on the exchange box. What is even wierder is that the laptop users A. have large exchange store mailboxes, but B. Also have the largest psts. Some will have over 7 GB total of email store mailbox and their psts files. They keep emailing each other documents or with customers. I ran a program that told us that of our 75 GB of our exchange store, 95% of those are attachements. We probably have another 70 or so GBs of PSTS just on our main file server, not our remote sites.

If we just had enterprise Vault we wouldn't have this problem.

so if you're running exchange server, there's no 2 gb limit on pst's?

no outlook 2003 you can go beyond the 2 gb limit. People still don't go beyond that, they will just create another one.

which hp switch?

you need a router in there.

you also need to buy cisco.


You're such a cisco goon..... ;)

cisco has enabled me to live a very lavish lifestyle.

there's no way that i'd be living as rich if i'd finished my degree in something else.

now if you excuse me, i have to RMA about 70k worth of parts that are piling up on my desk.


Why would I put a router on a LAN? WE use procurve 2626 switches

Cisco caused me to stay up from midnight to 10am this morning. Actually it was a couple of typos by a well paid CCIE. Granted these were only 2 typos in a MASSIVE 6513 config, but they were pretty important typos. (Both involving server ports) Ugh...

Oh well, I'm the junior guy payin my dues. Need that resume bling and setting up redundant 6500's in a 24x7 environment sure doesn't hurt.

I also have way to much $$ in gear sitting on my desk. Couple 2821's, a 3845, ATM cards, 2940's. I suprised nothing has walked actually. :)

Network Hardware Nerds ;)

Kidding, I have my share, but it is only for the small/med level stuff.

I will be working on a crazy ass project that includes over 80 servers running Citrix on a Colo.

if your network is connected to the interweb, then you have a router in that mix.

one day the bosses will realize that their cost savings in switch hardware is not worth the issues you're describing.


We have routers and we have internet access but this is just two network segements in my LAN that i'm having difficulty connecting.