Linking a switch and a router
Discussion
I'm just setting up a new office and have installed virgin business broadband with their router. I've also got a 48 port switch coming tomorrow (Cisco SG200 50FP, for anyone who's interested!).
If I plug the router into the switch, do I just need to switch off DHCP on the router to allow the switch to control everything?
Is there anything specific I need to consider? Initially there'll be 6 of us using the broadband for VoIP and data, using PoE to power the phones and making sure the switch prioritises voice traffic.
I'm relatively IT literate but don't want to miss something obvious in the setup.
If I plug the router into the switch, do I just need to switch off DHCP on the router to allow the switch to control everything?
Is there anything specific I need to consider? Initially there'll be 6 of us using the broadband for VoIP and data, using PoE to power the phones and making sure the switch prioritises voice traffic.
I'm relatively IT literate but don't want to miss something obvious in the setup.
Quick skim of the documentation doesnt scream "this is a switch that does DHCP", but I might be wrong. The Ebuyer etc links come back at the best part of a grand, which is erm, quite a lot for a small office. Good kit though.
If I'm right, leave DHCP on in the router, lock that down, and just use the switch as a switch.
If I'm right, leave DHCP on in the router, lock that down, and just use the switch as a switch.
janesmith1950 said:
...6 of us using the broadband for VoIP and data, using PoE to power the phones and making sure the switch prioritises voice traffic.
Your switch maybe the more expensive piece of kit but by definition the router has more responsibility than a switch so have the router handle the DHCP.However by the sound of it DHCP will be the least of your problems :-)
You're right of course. If I'd had the time I'd have done exactly that. I've had a window of opportunity to move offices and had to react accordingly.
I got access to the property yesterday, we move in on Saturday and begin working from it on Monday. The ageing 48 port switch we inherited with the office doesn't do PoE (essential), and anything I buy now needs to cope with expansion later this year.
A lost day trading, by the phone team being unable to function, would cost us around £4k in lost profit. Not a lot by some standards, but enough to say spending £300 more than I needed to on a switch that's reasonably certain to be capable of what I need for the next 12 months, is not such a big deal in the grand scheme of things.
I appreciate to IT bods here it's a bit like the proverbial 17 year old in General Gassing asking if the Caterham R500 he's ordered has cruise control and can tow a horse box.
Thank you all very much for your help and if I create an IT disaster zone I'll be back to let you know and give myself 50 internet lashes.
I got access to the property yesterday, we move in on Saturday and begin working from it on Monday. The ageing 48 port switch we inherited with the office doesn't do PoE (essential), and anything I buy now needs to cope with expansion later this year.
A lost day trading, by the phone team being unable to function, would cost us around £4k in lost profit. Not a lot by some standards, but enough to say spending £300 more than I needed to on a switch that's reasonably certain to be capable of what I need for the next 12 months, is not such a big deal in the grand scheme of things.
I appreciate to IT bods here it's a bit like the proverbial 17 year old in General Gassing asking if the Caterham R500 he's ordered has cruise control and can tow a horse box.
Thank you all very much for your help and if I create an IT disaster zone I'll be back to let you know and give myself 50 internet lashes.
crmcatee said:
6 of you and you're going for a 48 port switch !!
What's wrong with a 12 port.
What's wrong with a 12 port.
Nothing wrong with what you've bought at all. That's the going rate for an enterprise grade PoE switch!
Always overestimate how many network points you'll need!
You'll need to learn some Cisco commands though - if you want to do it right (it sounds like you do) then you might wanna think about separating the voip from the workstations with a couple of VLANs and apply QoS on the gateway? If you do this, then you will need to use the DHCP on the switch (If it has it, probably not - I haven't looked? The Virgin router won't understand IP helpers or even allow multiple DHCP scopes)
You don't have to do that of course (it does get complicated quite quickly), but it can help to prioritise traffic further down the line as you expand the network.
WinstonWolf said:
6 PC's, 6 phones, one uplink, BOOM 
I know, Always provide a bit of capacity but 48 does seem excessive without any indication of growth.
You do know you can plug your PC into the back of the phones don't you which halves the amount of ports you actually need although you will need to setup VLANs for that.
Nice switch, but if you don't need PoE on all 48 ports it's massively overkill.
That switch uses a web based management interface which will be a bit mystifying if you aren't familiar with switching technologies etc. I'm not even sure it has a wizard.
Cisco SG200-50FP is a layer 2 switch too, so I'm not sure what kind of DHCP server support it has, if any. I wouldn't advise running a DHCP server on a layer 2 device, personally.
That switch uses a web based management interface which will be a bit mystifying if you aren't familiar with switching technologies etc. I'm not even sure it has a wizard.
Cisco SG200-50FP is a layer 2 switch too, so I'm not sure what kind of DHCP server support it has, if any. I wouldn't advise running a DHCP server on a layer 2 device, personally.
I've been stung plenty of times thinking 8/12 etc. ports will be enough and ended up having to replace or daisy-chain. If I'm ever in the OP's position I'd go with the biggest I could afford too.
Thinking about fiddling with Cisco settings gives me flashbacks though, although I would hope that things have moved on considerably from the woeful Java IOS version I used to have to endure.
Thinking about fiddling with Cisco settings gives me flashbacks though, although I would hope that things have moved on considerably from the woeful Java IOS version I used to have to endure.
crmcatee said:
WinstonWolf said:
6 PC's, 6 phones, one uplink, BOOM
I know, Always provide a bit of capacity but 48 does seem excessive without any indication of growth.
You do know you can plug your PC into the back of the phones don't you which halves the amount of ports you actually need although you will need to setup VLANs for that.
I prefer separate voice and data networks wherever possible but that's just me. It also means I can offload phone support to someone else 
WinstonWolf said:
crmcatee said:
WinstonWolf said:
6 PC's, 6 phones, one uplink, BOOM
I know, Always provide a bit of capacity but 48 does seem excessive without any indication of growth.
You do know you can plug your PC into the back of the phones don't you which halves the amount of ports you actually need although you will need to setup VLANs for that.
I prefer separate voice and data networks wherever possible but that's just me. It also means I can offload phone support to someone else Gassing Station | Computers, Gadgets & Stuff | Top of Page | What's New | My Stuff