HP 2510-24 stack... how to cable?

[gshaw]

We've finally started to recable to remove the current mess of long CAT5 runs from each wall port to a central set of switches (Allied Telesyn blehhh) being replaced with HP 2510-24 units in the rooms running back to the main HP 4104GL that the servers are connected to.

 

Workstations are running 100MB CAT5e (cabling guys saw no real need for Gigabit to desktops at this time)

 

At the mo we've just maxed out the first switch so for the next room in the area I'm guessing another unit will need to go in there (was warned off the 48 port ones). I'm guessing I'll need to make a stack of the 2 HP units, read the manual for how to do it via the HP software but really just wanna check the cabling.

 

Is it just basically a link from one of the Gigabit CAT6 ports down to the next switch, cascading all the way to the bottom?

 

Tried to read this I found on search but HP moved the link (why do they always do that?!?!)

http://www.hp.com/rnd/pdfs/Stacking_White_Paper.pdf

 

Also, the current link back to the main switch is CAT5e as well, should it ideally be Gigabit, just thinking about traffic speeds for say 30-40 clients...

 

Not really designed the cabling backbone before so any advice appreciated.

 

Cheers

Edited April 21, 2008 by gshaw

[Geoff]

Ideally, you want each switch individually linked back to your 4204. With, again ideally, one switch serving each room. (This is what I'm intending to do here..).

 

However, you can cascade the switches and have a single link back like you plan. Just be aware you are creating a bottleneck there.

 

For ultimate resilience, you can enable STP and do both of the above methods, allowing each switch to have multiple redundant routes back to your 4204.

[gshaw]

What are you using to link the switches back to the main cabinet, definitely don't need fiber to do that but should it be Gigabit rather than 100MB?

 

Other thing to mention is that we have a fibre linking the server room switch to the other end of the building, room cabs then would be coming off that switch.

 

So basically in text art...

 

Server -----------FIBER---------Far End main switch-----room cabs

Room

Main

Switch

l

l

l

Servers

[bossman]

Star topology:

Core switch/s centralised, All cab switches connected via fibre giving 1Gb backbone, workstations and peripherals connected to cab switches via 100Mbps cat5e or 6e for future.

For redundancy have core switches duplicated and ready to plug in at a moments notice so instead of 5 working days support it is just minutes. A tad expensive but what cost the loss of a core switch.

For example we lost one of our Catalyst core switches 3 weeks ago and due to this fact was back up and running within the hour got a great thank you from Headteacher and all staff.

VLANs are ok from cab to cab but for core switches a near hot swap is more reliable.

[Geoff]

Well here I am using CAT5e, so I can run 1Gbit over the links between our 4204 and the 2650's (each room has 30+ PCs) as the 4204 has a 24port 1Gbit module and the 2650s have 2x1Gbit ports.

 

You really don't need that fibre link unless the link is going between buildings? If it isn't then you can make do with additional Cat5e links. If however it is, you must use extra fibre links, or upgrade the speed of your existing fibre.

[gshaw]

So Cat5e is OK to link the cab switches back to the main switch? Should be Gigabit though if I'm reading right?

 

As far as I know the fiber link was put there as the run is a bit too long for Ethernet without a repeater so that seemed easier in the long run...

 

Other question I got at the mo - our 4104GL only has a 6 port Giagbit module in at the mo, which is filled up by the servers. Do you think it's worth buying the extra module to expand it in order to patch in the cab switches or just buy a newer switch that comes with more ports anyway? Just thinking about the age of the unit and price of expansion cards vs price of newer (more reliable?) unit...

 

Thanks for your advice so far