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We may have overloaded the network


Tripredacus

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Only thing I can say is you get what you pay for. I looked at the TrendNet options, all of them - definitely not what I'd call top-flight stuff... I'd rather run Netgear if I was gonna go workgroup switching than TrendNet, honestly, as at least their gear is quality for the money. Otherwise you suck it up and get HP ProCurve or Cisco kit and be done with it, and they'll work rock-solid forever and give you good management options. The most important thing to remember when buying a workgroup unmanaged switch is that you will get what you've paid for. When you shell out for something with quality switching fabric and a beefy backbone, and a good OS underneath, you also (should) get what you pay for. I'd say the smart switches from Netgear would be your best upgrade if they balk at a "real" managed switch, as you'll definitely get better performance and some management, which is always better than none.

As to managed switching, there's a reason those things cost so much - switching packets isn't something simple when you start to get heavy traffic, and it can really come down to the quality of the underlying OS and the way it uses it's switches horsepower (not to mention whether it's "smart" or "dumb") that makes a difference in performance on a utilized LAN. Considering the network guy didn't know you couldn't use link aggregation with an unmanaged switch, I'm not surprised you weren't able to convince the purchasing department to spend money on good (hardware) help either. Good luck to you, you might be the only one with a clue where you work... :blink:

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Sometimes I think its less "a clue" but more "a care" about things. I've always been the kind of guy that wants to make things more efficient.

Yes Netgear was the place we looked because they are our #1 supplier for networking gear. The other one is CNet and they are garbage. I will do some more research I guess, since my question wasn't directly answered. We basically need a way to keep gigabit clients running at gigabit when 100Mbps clients are on the network. We can get 40% util from the server if all are gigabit, which considering mean limits and SMB is just fine. But running at 1% util when 10/100 clients are present delays us greatly.

The servers don't do much either, since this is only for production and not enterprise work. Yes a domain exists (only because WDS requires it) but there is only 1 domain member. The only thing the DC does is DHCP and both servers act as file servers, and there is no internet access.

I still remember when MS told us we needed to go to managed switches, but management nods and agrees and does nothing until someone speaks up. And I am that person so I get yelled at for speaking up sometimes!

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  • 6 months later...

Oof it really kicked the bucket today. It probably happened over the weekend or so. One of the switches was not communicating with the server at all, but the other switch was OK. I rebooted it and nothing, so then connected the Wind to the line and it worked. To think maybe the switch was bad, I swapped it out. Then the new switch wasn't working either.

So of course we try another network cable and then that switch is up again! Easy fix right? Well not unless you try to do something with it, which then caused the entire network to drop! So I disconnected the new wire and the other switch magically starts working.

So something happened over the weekend that caused part of the network to fail. Also very interesting (via testing) I found that if both switches were connected (when the network failed or ran very slow) the Team broke! If I only have 1 switch connected, the team does not break.

Yes I still make the case to get some managed switches, hopefully this will happen soon. However, what can cause the team to break like this?

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Sounds like a memory error on the "broken" switch, honestly - we had a Cisco that was doing the same sorts of things when spanning tree was enabled. Some of the internal memory was bad, and the switch was replaced.

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Sounds like a memory error on the "broken" switch, honestly - we had a Cisco that was doing the same sorts of things when spanning tree was enabled. Some of the internal memory was bad, and the switch was replaced.

Replacing the switch didn't make a difference. I thought that too. We're having someone look at it in the morning, hopefully its just something I overlooked.

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Your issue sounded like a loop got created!

I was kinda reading through the earlier posts in this thread. Have you replaced those switches with managed switches yet? We use Extreme Networks switches. Very fast, very easy to configure and not nearly as expensive as other options (yes, still expensive, but not nearly as much as other alternatives). If you aren't doing any VLAN management (which you currently aren't since they're unmanaged switches) and don't need Layer 3 managed switches you can look at their X150 (10/100) and X350 (Gigabit) line. They're Layer 2 only and can't be stacked, but they're also much cheaper. We use a combination of X450's, X250's and X150's.

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Your issue sounded like a loop got created!

I was kinda reading through the earlier posts in this thread. Have you replaced those switches with managed switches yet? We use Extreme Networks switches. Very fast, very easy to configure and not nearly as expensive as other options (yes, still expensive, but not nearly as much as other alternatives). If you aren't doing any VLAN management (which you currently aren't since they're unmanaged switches) and don't need Layer 3 managed switches you can look at their X150 (10/100) and X350 (Gigabit) line. They're Layer 2 only and can't be stacked, but they're also much cheaper. We use a combination of X450's, X250's and X150's.

Yeah I left the "loop" part out as I wasn't sure how to word it politely... :unsure:

We still are just using the old switches, except now the plan has been upgraded to getting managed switches as well as patch panels. Yes we just have Cat6 running through the ceiling and under tables. We do not need VLAN or anything crazy. This network has is isolated, we only want to be able to have switches that allow 100Mbps clients to run at 100 and the gigabit to run at gigabit at the same time. Currently, if a 100Mbps client is running (which it will if we use DOS Ghost client) the entire LAN drops to 100! Then what happens is that the gigabit clients end up timing out and the server will eventually cease to see that particular segment or the entire network.

This wouldn't be such a big issue if we didn't have to use Ghost, but we still must use it to image XP machines with HD based recovery, since Imagex can't do it. And all the DOS NDIS drivers for Ghost run gigabit NICs at 100. Also, some onboard NICs (not Intel, but moreso Broadcom, RTL, etc) do not run at gigabit speed unless Windows is installed. So for example, a gigabit NIC will run at 100 during PXE or will if its just sitting in the BIOS or any pre-OS installed state, it will report to the switch its 100, make the light orange, then put Windows on it, install the driver and the light turns green/gigabit. Really annoying.

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Sounds like some bargain basement switches there - a 100Mb client shouldn't knock the switching backplane down to 100Mb for ALL ports. That's just crazy talk :).

Well when we use Ghost, its not coming from the 2008 server. The host for Ghost is 2003. So Ghost "Multicast" is emulated, and 2003 doesn't do multicast. The end result is that 2003 Unicasts the image to all interfaces, which is why the entire network slows down.

I summed it up today in discussion, one of my underlings said "i'll wait until later to run this Ghost because I don't want to slow down the network" and I responded no go ahead, the more it gets slow and breaks, maybe we'll get lucky and management will open the wallet for the right hardware for us. :whistle:

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This wouldn't be such a big issue if we didn't have to use Ghost, but we still must use it to image XP machines with HD based recovery, since Imagex can't do it.
What specifically are you doing that imagex can't handle with XP? Are we talking about using the Ghost software to make backups that you're restoring (aka, not sysprep images)?
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This wouldn't be such a big issue if we didn't have to use Ghost, but we still must use it to image XP machines with HD based recovery, since Imagex can't do it.
What specifically are you doing that imagex can't handle with XP? Are we talking about using the Ghost software to make backups that you're restoring (aka, not sysprep images)?

Recovery partitions! :whistle:

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Yeah I left the "loop" part out as I wasn't sure how to word it politely... :unsure:

You really need some managed switches. :)

I'll go back to the Extreme switches again. They have a feature called ELRP--Extreme Loop Recovery Protocol. It's not on by default but once configured it will detect a loop and automatically disable the looped ports. If you have their management app--EPICenter--you can configure it to forward switch events to you via email and/or text message so you'll know immediately when that loop is created and which ports it was created on.

It also helps to be able to disable ununsed ports so someone can't just walk up and plug in.

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