MASSIVE drop in speed between being plugged into the main switch and a network port

[AndyCan]

I've come across a problem in that when im plugged into the main switch and do speedtest i get 46meg download speeds. From the switch cabling goes to a patch panel and then to network ports over the building. if i plug into the network ports in rooms and run speedtest i get around 10meg download speeds. So i'm clearly losing a massive amount of speed through poor wiring?

 

If so what does that mean, is there anything i can check or is it a case of i'd have to get someone in to rewire the whole place? What is it that could have been done so bad to account for this kind of loss do you think so that i can look out for it in the future?

 

Any help would be appreciated.

[glennda]

my guess would be there is either bad patch cables or bad termination.

 

Is windows saying it has a 10mb connection from task manager/networking?

 

get a network tester and test each port

[AndyCan]

when i look in task manager it says Link Speed = 100mbps. That what you mean? What exactly will a network tester tell me and then what can i do with that information afterwards in order to fix the problem?

[mattx]

Duplex mis-match

[glennda]

How are you judging that you are only getting 10MBs?

 

You will find that 100Mb/S is actually only 12.5MB/S do you can only transfer 12.5MB a second over a 100Mb/s connection.

Explained the difference is Megabits and megabyte i.e Mega-Bit = 1,000,000 bits and Mega-byte = 8,000,000 bits

 

Are the switches 10/100 or 10/100/1000?

[AndyCan]

I was investigating poor download speeds. From my desktop i was getting roughly 10meg download speed on our 50meg line. So i plugged into the router and got 48meg. so i then plugged into the switch and got 48meg again. The cabling then goes from the switch to the patch panel, to wall points around the building and then to some small switches which then all workstations plug into. I plugged straight into the wall ran speedtest and was getting 10meg as apposed to the 48 when plugged into the router and switch. the main switch is a gigabit switch but as i get max speed when plugged directly into this, this isn't the problem, it surely must be something to with the patch panel or wiring in the walls to the wall point?

[glennda]

Duplex mis-match

 

Surely that would happen if plugged directly in or not?

[glennda]

I was investigating poor download speeds. From my desktop i was getting roughly 10meg download speed on our 50meg line. So i plugged into the router and got 48meg. so i then plugged into the switch and got 48meg again. The cabling then goes from the switch to the patch panel, to wall points around the building and then to some small switches which then all workstations plug into. I plugged straight into the wall ran speedtest and was getting 10meg as apposed to the 48 when plugged into the router and switch. the main switch is a gigabit switch but as i get max speed when plugged directly into this, this isn't the problem, it surely must be something to with the patch panel or wiring in the walls to the wall point?

 

Sounds like your router has a gig port and so does the laptop but the switching is only 10/100 therefore you would only be able to transfer a max of 12.5Mb to each connected client

[mattx]

The way I read this is the problem he is facing is thus:

 

OK Speed going into router and the switch the router is going into.

Not ok speed when plugged into another switch [ he mentions small switches ] which sort of sets alarm bells ringing as they are most probably un-managed so you can't monitor any ports or set any duplex settings on any up-links to test. Also no mention of any QOS which may be in place on so really pi55ing in the wind but the first thing I would check [ if possible ] and going on past expereince - I would first look at duplex settings and if possible dump the un-managed switches.

Of course testing cables is always a good idea and don't forget to check the settings on your NIC in the laptop / PC and turn your wireless OFF if that's on, I've seen some weird stuff when it comes to that.

[AndyCan]

ok let me be clear:

 

Net Connection into SonicWall Router

Plug laptop into SonicWall Router - Speed fine

SonicWall goes into gigabit switch

Plug laptop into gigabit switch - Speed fine

Switch goes to patch panel

Patch panel goes to network ports on the wall around the building

Plug laptop into network ports on wall - Speed crap!

 

So ignore the small unmanaged switches as the speed loss occurs before they even come into play. The problem is surely wiring between the patch panel and the wall ports. But what i do to try and correct this i dont know, can it be corrected or would everything need re-wiring between patch panel and wall ports? but it would be nice to know exactly what the problem is

[glennda]

The way I read this is the problem he is facing is thus:

 

OK Speed going into router and the switch the router is going into.

Not ok speed when plugged into another switch [ he mentions small switches ] which sort of sets alarm bells ringing as they are most probably un-managed so you can't monitor any ports or set any duplex settings on any up-links to test. Also no mention of any QOS which may be in place on so really pi55ing in the wind but the first thing I would check [ if possible ] and going on past expereince - I would first look at duplex settings and if possible dump the un-managed switches.

Of course testing cables is always a good idea and don't forget to check the settings on your NIC in the laptop / PC and turn your wireless OFF if that's on, I've seen some weird stuff when it comes to that.

 

Yup Duplex Mis-match is a good idea - When i first read the post it sound like when he plug pc-switch he got 48mb when he plugged pc-wall-switch he got 10 (which made me think cabling). Plugging directly into a router which has a gig port would mean he could use the full 50Mb line whereas going via the switch at 100Mbits/s would mean only a max of 12.5Mbytes/s down the cable.

 

I made that mistake a while ago when I thought my core transfer speeds where slow.

[glennda]

So ignore the small unmanaged switches as the speed loss occurs before they even come into play. The problem is surely wiring between the patch panel and the wall ports. But what i do to try and correct this i dont know, can it be corrected or would everything need re-wiring between patch panel and wall ports? but it would be nice to know exactly what the problem is

 

 

it does sound like a cable problem. Gigabit requires more pairs in the cable i think then 100mb. so worth just checking the connections using a cable tester something like this

 

But the reason you will only get ~10Mbytes to the machine on a a 100mbits connection is my point about the difference.

[AndyCan]

The cabling coming out of the back of the patch panel i can see is cat 5.e so that should be good yes?

 

So could it be the way its wired either into the patch panel or the network sockets on the wall? or even the patch panel itself although im not sure what could go wrong with that, surely it either works or it doesn't?

[glennda]

The cabling coming out of the back of the patch panel i can see is cat 5.e so that should be good yes?

 

So could it be the way its wired either into the patch panel or the network sockets on the wall? or even the patch panel itself although im not sure what could go wrong with that, surely it either works or it doesn't?

 

Cat 5 E will take gigabit. There is lots of things that could be the problem with the cabling but is this everywhere or only on a couple of sockets? You might find that somebody has terminated them in an incorrect way meaning that there is a cross over in the cables somewhere. A cable tester will tell you if the cable is miss wired.

[AndyCan]

its everywhere. ok so maybe i'll have to get a cable tester then but even if i find the problem, its going to be something a professional i think would have to come in and correct, so maybe i should just get them in anyway and they'd have everything already to dtermine the problem

[CyberNerd]

So ignore the small unmanaged switches as the speed loss occurs before they even come into play.

 

Try unplugging these. just on the off chance they are causing issues, network loops etc.

 

It seems difficult to imaging that ALL the network ports are mis-wired, but a cable tester would tell you.

 

can you do a constant ping to the switch? and do ALL ports work ok when plugged directly into the switch?

[mattx]

Yup Duplex Mis-match is a good idea - When i first read the post it sound like when he plug pc-switch he got 48mb when he plugged pc-wall-switch he got 10 (which made me think cabling). Plugging directly into a router which has a gig port would mean he could use the full 50Mb line whereas going via the switch at 100Mbits/s would mean only a max of 12.5Mbytes/s down the cable.

 

I made that mistake a while ago when I thought my core transfer speeds where slow.

 

Hang on, he's taken the small switches out of the problem now.....

[AndyCan]

Try unplugging these. just on the off chance they are causing issues, network loops etc.

 

It seems difficult to imaging that ALL the network ports are mis-wired, but a cable tester would tell you.

 

can you do a constant ping to the switch? and do ALL ports work ok when plugged directly into the switch?

 

I can unplug everything but i'll have to do that out of hours so cant test that just now.

[CyberNerd]

I can unplug everything but i'll have to do that out of hours so cant test that just now.

 

I think you will need to try it, it seems too strange to be a cabling issue on all cables. I would have said a network loop overloading the gigabit switch is more likely, unless you can be 100% sure it's fine when plugged to all ports on the gig switch.

 

Did you try a constant ping yet "ping xxx.xxx.xxx.xxx -t" where xxx is switch IP ?

[AndyCan]

I think you will need to try it, it seems too strange to be a cabling issue on all cables. I would have said a network loop overloading the gigabit switch is more likely, unless you can be 100% sure it's fine when plugged to all ports on the gig switch.

 

Did you try a constant ping yet "ping xxx.xxx.xxx.xxx -t" where xxx is switch IP ?

 

Yep if i ping its pretty much constantly <1ms.

 

Monday morning i'll take everything out of the main switch then walk round every wall point and test and see if its consistent

[CyberNerd]

Yep if i ping its pretty much constantly <1ms.

 

Sounds even more strange. Can you log into the switch?, check that it's not something dumb like certain ports being limited to 10Mb.

[AndyCan]

Sounds even more strange. Can you log into the switch?, check that it's not something dumb like certain ports being limited to 10Mb.

 

all are set to 100 Full. just checked.

[AndyCan]

all are set to 100 Full. just checked.

 

sorry apart from the fiber port which is 1000 Full and another port set to 1000 but i'll need to check why and whats plugged into, but everything else is 100 Full, nothing set to 10

[glennda]

all are set to 100 Full. just checked.

 

hence my point about the 12.5Mb limit although it is stange that you can get 48mb when directly connected to switch - you are not putting laptop in gig slot on device when you test that?

[AndyCan]

hence my point about the 12.5Mb limit although it is stange that you can get 48mb when directly connected to switch - you are not putting laptop in gig slot on device when you test that?

 

nope tried it in a few which are all set to 100 FULL