Core and Edge Switches upgrade

[maxrebo]

Hi,

We have some money to upgrade our switches, can anyone give me advice on our current spec and what models need upgrading.

I'm right in thinking that the core switches need an upgrade as these are a quite old model. Could anyone suggest what they use for their Core switches, I would like to stay HP.

Below is our switch setup, any advice would be helpful

 

Core2 x 3Com 5500g

Edge

3Com 5952

HP v1910 48g

3Com 2952+

3Com 3250

[pantscat]

The HP 5400 series are really solid core switches - I'd definitely recommend these.

 

For the edge, it really depends on what features you need. Do you use PoE? VoIP? Anything like 802.1x auth?

[tmcd35]

I've been working with Net-Ctrl on a managed Wi-Fi project. We've needed to do some upgrades to both core and edge switching within the project. They've given us some really good pricing on Allied Telesis kit, which I have to say I'm impressed with - at least on paper.

 

We're going to be using some Stacked x610's for the core and websmart GS950's at the edge. Price for 9 switches (3 core, 6 edge) compares favourably against 1x HP 5400 series core! (by the time we've kitted out what we need in modules, etc)

[maxrebo]

Hi,

Yes i have heard the 5400 series comes highly recommended, what model do you have?

With regards to the edge switches, we have a number of HP POE switches currently so we can use these for POE, would probably just need some thing like we currently have such as the HP v1910, my only question with these are, is it worth going for a newer spec or do you think these are ok for a direct replacement for the 3 Com switches?

 

Regards

[sonofsanta]

We replaced our 3COMs (we used to have a 5500G at the core as well) with the HP Comware switches - that is, HP bought 3COM, so we put that range out. It meant we could re-use existing fibre SFPs which saved thousands of pounds.

 

We stacked to HP A5800s at the core as a replacement for the 5500G, and we use A5120s (both POE & non-POE) at major cabinets. Smaller cabs that don't justify a level 3 switch, e.g. those supplying a single IT room, get an HP-1910.

[pantscat]

I used to use the 5412 and 5406zl. The 2920s are pretty decent for edge switches too.

[njc235]

It all depends on your vision for the network. Some questions to ask are; Are you looking at a 10G backbone to all or some edge cabs. Do you intend to have VOIP requiring QoS from the edges. Do you have or will you have BYOD wireless. What is your appetite for CLI or GUI. Do you prefer one particular vendor.

 

HTH

[maxrebo]

I think my first few question`s to be answered would be -

Would i benefit much from replacing all of the 3 Com edge switches and replace them with say HP v1910`s?

Or am i not going to benefit much from doing that and concentrate more on the Core switches?

 

Regards

[njc235]

Hi Max

 

I would say always start at the core. Everyone will benefit and you will be a hero. Next time you ask for funds for something it will be easier too! A decent core, whether Procurce 54xx or Comware 5800 will support aggregated links so any spare fibres can me utilised to increase performance from the edges.

 

The 1910s are being phased out for the 1920. If you are looking toward a 10G backbone, you might consider the 2530 which have SFP+ uplink ports.

 

HTH

Nick

[pantscat]

What speed is the link from the core to the edge?

 

What are you trying to achieve? better performance? Newer kit for warranty purposes? Easier management?

[maxrebo]

What speed is the link from the core to the edge?

 

What are you trying to achieve? better performance? Newer kit for warranty purposes? Easier management?

 

Link is 1gig

Better performance yes and generally want to get rid of the 3Com switches (but i don't really have any argument for this other than they are old)

[pantscat]

If they're old and out of warranty then that is a reasonable enough reason.

 

If it's a 1gig link then there's little point in having 1gig to the desktop, unless you're planning on upgrading to 10gig at any point.

[tmcd35]

If it's a 1gig link then there's little point in having 1gig to the desktop, unless you're planning on upgrading to 10gig at any point.

 

That's not all together true. A lot depends on the contention ratio of the uplink, if/how the network is vlan'd, and there's also the possibility of LACP trunking. As I mentioned above, out WiFi upgrade project for the summer has somehow turned into a semi-major switch refresh at the same time.

 

What I've found as I've actually gone round looking at the the switches, is that 10gig is still largely too expensive for the edge, and a combination of good vlan'ing and LACP trunking the uplinks provides more than enough bandwidth to support 1gig to the desktop, especially since the vast majority of users would never use all the bandwidth available to them anyway.

[pantscat]

Yes, perhaps I over simplified it a tad - LACP trunks would make a difference, as would contention ratios.

[mjk]

That's not all together true. A lot depends on the contention ratio of the uplink, if/how the network is vlan'd, and there's also the possibility of LACP trunking. As I mentioned above, out WiFi upgrade project for the summer has somehow turned into a semi-major switch refresh at the same time.

 

What I've found as I've actually gone round looking at the the switches, is that 10gig is still largely too expensive for the edge, and a combination of good vlan'ing and LACP trunking the uplinks provides more than enough bandwidth to support 1gig to the desktop, especially since the vast majority of users would never use all the bandwidth available to them anyway.

 

I think it is more important to have routing setup on the edge switches if you have 1Gb desktop but only 1 or 2Gb backbone uplinks.

This would mean that routing is done nearer to the desktop machines and will save bandwidth on traffic flowing to and from the core switch (to make the decision about where to route).

It also makes problemshooting more easy if you have areas of the network 'cordoned off' from the core.

 

Of course; if everyone wanted to use the 1GB desktop at the same time (when imaging for example) you would still bottleneck it!

[sonofsanta]

Switches to provide 1GbE to the edge are not that much more expensive than 100MbE now, and usually better switches for it as well. If these switches are going to be in for ten years, you should be putting 1GbE in unless money is so unbelievably scrapingly tight that you have to cut what corners you can.

 

10GbE, on the other hand, is still expensive at the core, but finally at the point where it's not beyond consideration. You should at least plan for the expansion in that direction, even if you don't implement for another few years.

Edited May 22, 2015 by sonofsanta

[cpjitservices]

I've been working with Net-Ctrl on a managed Wi-Fi project. We've needed to do some upgrades to both core and edge switching within the project. They've given us some really good pricing on Allied Telesis kit, which I have to say I'm impressed with - at least on paper.

 

We're going to be using some Stacked x610's for the core and websmart GS950's at the edge. Price for 9 switches (3 core, 6 edge) compares favourably against 1x HP 5400 series core! (by the time we've kitted out what we need in modules, etc)

 

Having worked with Allied Telesis kit I can tell you that they are good switches, solid and reliable and support is pretty good if you need it.

[richbrowncardiff]

Having worked with Allied Telesis kit I can tell you that they are good switches, solid and reliable and support is pretty good if you need it.

 

I can second that ! We have the 28 port Fibre AT-9000/28sp as our "Core" (All fibre comes back to this) then use a NETGEAR ProSafe GSM7212F-100NES for routing which is an L2+ switch. Both cost less than £2k and work really well. Network throughput average is around 80mbps on the network with 300 concurrent clients logged in. which considering theoretical max of 1gbe is 120mbps is pretty good imho. at the edge we have HP 1910's and i really can't fault any of it. servers go directly via a trunk of 2gbps to the Allied Telesis and honestly for what we need it works really well.

 

In future when we change our other switches i will buy all Allied Telesis as they offer great value and features

 

In the server Rack each server connects to a HP 1910 (4 x nics 2 in active mode to give 2gbps and the other 2 in standby for resilience)

[psydii]

Interesting new switch from HP.

 

HP 1950 Switch Series

 

Like the 1910/20 but with 10G uplinks. Looks a bit like the love child of the 1920 and 5500.

 

(as an aside has anyone else noticed the 5120-SI is the 1920 but in a blue/grey case and without the CLI disabled and the 5120-EI is the 5500 but without the advanced layer 3 stuff ?)

Edited June 2, 2015 by psydii

[sonofsanta]

Interesting new switch from HP.

 

HP 1950 Switch Series

 

Like the 1910/20 but with 10G uplinks. Looks a bit like the love child of the 1920 and 5500.

 

(as an aside has anyone else noticed the 5120-SI is the 1920 but in a blue/grey case and without the CLI disabled and the 5120-EI is the 5500 but without the advanced layer 3 stuff ?)

 

I was briefly excited until I saw the price.

 

48 port 1910: £340

48 port 1950: £1194

 

Maybe I'll wait for the price to drop, then...

[tmcd35]

I was briefly excited until I saw the price.

 

48 port 1910: £340

48 port 1950: £1194

 

Maybe I'll wait for the price to drop, then...

 

I don't know, those prices look extremely reasonable to me. Might be a bit less than the Allied Telesis quotes I've not long green lighted. Certainly a good option for the edge in future upgrades.

[sonofsanta]

I don't know, those prices look extremely reasonable to me. Might be a bit less than the Allied Telesis quotes I've not long green lighted. Certainly a good option for the edge in future upgrades.

 

I've not looked at 10GbE switches too much yet (need to upgrade a load of fibre next summer first) but 2 ports are tripling the price, and that's before you buy the SFPs at around £300. So the prices are probably reasonable in context of other 10GbE switches, I don't know yet, but they're intimidating in context of 1GbE switches.

 

Hopefully the next two to three years will see it fall to a smaller premium, though, it seems like we should be near that tipping point.

[DMcCoy]

Take care with the 1900s I can't find the ARP table limit for the 1950s but the earlier ones were only 256 entries.

[ITGURU]

Had HP gear when on 1GB, but now fully D-Link 10GB backbone as gave a better service and advice on the upgrade. Came to site and demonstrated how we could gradually migrate from 1 to 10 gig where as HP wasn't interested, just wanted to sell the kit.

 

Whatever you go for make sure it's got Loopback Detection as a feature...saves students taking down your network when messing with cables!

[tmcd35]

I've not looked at 10GbE switches too much yet (need to upgrade a load of fibre next summer first) but 2 ports are tripling the price, and that's before you buy the SFPs at around £300. So the prices are probably reasonable in context of other 10GbE switches, I don't know yet, but they're intimidating in context of 1GbE switches.

 

That's why I scaled back our plans here to offer 10Gb at the core now ready for future edge/server (more likely server) upgrades. I was thinking of 10Gbe to one or two edge locals but realised bonded 1Gbe is a lot cheaper and would give us plenty of bandwidth in the short to medium term.