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[ericabiz]

We currently have a Cisco 2924 (24 ports) and a 3Com Superstack 10/100 12-port switch. Both have served us well; however, since we now have about 30 ports connected, I'm looking for something a bit more advanced.

I'm looking for a switch that does VLANs (that a non-router guru like me can set up; I'm not afraid of the command line... just have to know what to type there!) and that does bandwidth limiting (i.e. I can log in and say that port x should be limited to any arbitrary value such as 10Mbit or 25Mbit.) I also want a switch with 48 ports or more or 2x24-port switches that can be chained together. I'd also need SNMP, but as both of our current switches already have this, it seems like a given with any reasonably high-end switch.

Another company is looking to get rid of an Extreme Networks Summit 48-port switch (model 15000.) Would this work for our purposes?

Of course, I'll hire someone to set this all up. I'm just looking for purchase recommendations right now.

[Papa Smurff]

First the good news, you don't need to be a router guru.
Switches are much easier to handle. Uh, never mind, I take that back.

Extreme is good, Foundry, HP, Cisco.
Problem is that I do not believe that L2 and L3 switches do traffic shaping. They do QoS stuff like giving priority but I'm pretty sure you need a L3 router to do CAR (Committed Access Rate) and Traffic-shaping or rate-limit stuff. For example, I have this on my routers fastethernet interface:
rate-limit output 5000000 650000 1250000 conform-action transmit exceed-action drop

This caps that interface to 5 megs.

You may want to check out Cisco works policy manager:
http://www.cisco.com/en/US/products/...080091bcf.html

[poisonrevers]

Well,

Geting your own IP's you'll be able to BGP, but I am not sure about the rate limiting. You may have to look into that. There might be 3rd party software out there to help you. I have actually had the priviledge of using quite a number of higher end equipment and Summit48's are good as well as maybe Cisco 2948 L3.

Try them. Superstack is garbage if you ask me and I'm not to keen on the 3com ones.

[ericabiz]

Hmm. I'm really looking for a solution that would not require us to get our own router, as that would be a single point of failure on our network, and one that could be very expensive to replace if something happened. I'd rather keep the routing done by Abovenet.

What are my options if I want to do rate-limiting, then?

Thanks!

[Papa Smurff]

Originally posted by Papa Smurff
First the good news, you don't need to be a router guru.
Switches are much easier to handle. Uh, never mind, I take that back.

Extreme is good, Foundry, HP, Cisco.
Problem is that I do not believe that L2 and L3 switches do traffic shaping. They do QoS stuff like giving priority but I'm pretty sure you need a L3 router to do CAR (Committed Access Rate) and Traffic-shaping or rate-limit stuff. For example, I have this on my routers fastethernet interface:
rate-limit output 5000000 650000 1250000 conform-action transmit exceed-action drop

This caps that interface to 5 megs.

You may want to check out Cisco works policy manager:
http://www.cisco.com/en/US/products/...080091bcf.html

After a discussion in a different forum it is safe to say that any switch that also has a routing function built into it can handle your traffic shaping needs. These are typically referred to as Layer 3 switches. Otherwise known as "switch routers".
The Summit 48 and 2948 L3 are both good choices. I hear the Summit is faster though because it is true wire speed.

[ericabiz]

Originally posted by Papa Smurff
After a discussion in a different forum it is safe to say that any switch that also has a routing function built into it can handle your traffic shaping needs. These are typically referred to as Layer 3 switches. Otherwise known as "switch routers".
The Summit 48 and 2948 L3 are both good choices. I hear the Summit is faster though because it is true wire speed.

So the Summit 48 that this company is offering to sell us would limit a port to a specific speed (an arbitrary one; not just 10Mbit or 100Mbit)?

I want to make sure of this, since this will be a large investment for our company. Not only will we have to buy the switch (which is expensive!), but we will also have to hire out to configure it and train our staff on how to use it. As an explanation, I run the business end of things (sales, marketing, etc.) and I've hired two technical gurus to maintain and support our systems, but unfortunately none of us are router gurus... and I don't want someone on staff to set up such a core aspect of our business as a "learning experience."

Thanks!

[Papa Smurff]

I can't speak as to Summit.
Cisco, yes.
It depends on the feature sets of the IOS versions that can be run on the particular route module inside of the "switch router".

You really should do some research on the particular models and see exactly what they are capable of.
Then make sure the particular OS versions support what you want to do.

[Mfjp]

Summit have rate-limiting as well, for both the basic L3 and the Full L3.

I have research this as well, the 2948XL - EN would also do this.

If u're looking for something cheap, the Nortel would do too.

[nectar]

Erica,

I'd recommend you use the 2948G-L3 its costs about ...$1900 or so on eBay, which will do basically what you'd like. It also can do vlan-tagging.

If you want to go the cheaper method you can add a zebra router above it and have it act as the L3 and then setup VLANS from the ZEBRA and have each of the 2924 ports use the assigned VLAN port that was given from the ZEBRA.

The Zebra method will save on you buying new switches, as long as there is a management system built into the switch. (I.E. Cisco, Extreme, Foundry)

[ericabiz]

I just called and spoke with a rep from Extreme Networks. He said he didn't have full documentation on the Summit 48 15000, but that it looked like it came with firmware version 4.0. Version 6.2 was the first one that supported per-port rate limiting... that's the version that comes with the 48i switches. He was unsure whether the 48 could be upgraded to support the latest firmware, but it appears unlikely.

Nectar, funny that you just mentioned the 2948G-L3... I checked out eBay and I saw one for sale there. It absolutely has everything we need; the datasheet says this:

The Catalyst 2948G-L3 supports per-port input rate limiting,output rate limiting, and traffic shaping on Gigabit Ethernet and Fast Ethernet interfaces. The per-port rate limiting feature provides the ability to rate limit the input and/or output traffic of a port. The traffic rate of the port is monitored. The conforming traffic is allowed, and the nonconforming traffic is dropped. The per-port shaping feature provides the ability to shape the output of a port. The output traffic rate of the port is monitored to verify that the traffic leaves the interface at the user-configured rate. When excess traffic comes into the switch, back pressure is applied from the modules to the switch fabric, and the excess traffic gets queued in the switch fabric. If the switch fabric queues overflow, the excess traffic is dropped. The minimum rate is 32 kbps, with a granularity of 32 kbps.

That's exactly what I'm looking for.

Guess I'll start ironing out the budget to work that in...

[s.h.a.zz.y]

I would check out the Foundry gear ... ( FastIron WorkStation 4802 PREMIUM )

Extreme is not that powerful on L3 side.

[narziss]

One thing to pay attention to on the lower end line of Cisco switches is resource exhaustion. If you are using such a device to facilitate actual Layer2 VLANs, Layer 3 SVI's and VLSM allocations, as well as QoS, you may very well run into an issue with exhuasting the unit. And when I say exhaust, try to picture a two pack a day smoker in the finishing stretch of the New York Marathon; it's not pretty. Once you have exhausted the switches onboard TCAM for VLAN/ARP and QoS, the CPU will begin to 'process' packets, rather than the hardware performing the forwarding. When this happens your network will perform in what would be considered a 'less than desirable' fashion.

If you have specifics about the network topology, and what will be connected to it, I'd be happy to offer suggestions based on my own experience and regrettable mistakes.

Regards,

[ericabiz]

Originally posted by narziss
One thing to pay attention to on the lower end line of Cisco switches is resource exhaustion. If you are using such a device to facilitate actual Layer2 VLANs, Layer 3 SVI's and VLSM allocations, as well as QoS, you may very well run into an issue with exhuasting the unit. And when I say exhaust, try to picture a two pack a day smoker in the finishing stretch of the New York Marathon; it's not pretty.

Well, we currently have something like 30 servers connected, and we add 5-7 new servers a month, so obviously something is going to have to be done fairly soon.

Most servers won't need VLANs or traffic shaping. I'd just like to be able to sell 10Mbit dedicateds, or limit a few particular customers to, say, 25Mbit to ensure that they don't take over the entire switch if their server gets slammed with requests.

What would you define as a configuration that "exhausts" the switch? Keep in mind that I really have no idea how a switch works on a technical level other than the fact that it moves packets from one place to another. I'm a business owner, not a CCIE.

[Gernot]

Originally posted by Simpli-Erica

What would you define as a configuration that "exhausts" the switch? Keep in mind that I really have no idea how a switch works on a technical level other than the fact that it moves packets from one place to another. I'm a business owner, not a CCIE.

Well, the 1948G-l3 won't exhaust that fast if you do not do much more than VLAN tagging and rate-shaping. This device has a fairly large backplane so you'll really have a hard time overloading it with basic L2 switching with some L3 extensions.
Just don't make the mistake of using the 2948G-L3 as a full router-replacement as it's still just a switch

I'd pick up a 2948G-L3 if you can get one at an affordable price

[rusko]

low end ciscos are not known to do rate limiting well. for this purpose, i would highly recommend smaller foundry fastirons. they have ACL-based rate limiting which works quite well. level 3 stuff does not work well enough to be used on any of the lower end switches, imho. forget layer 3, get a decent switch to do the switching.

paul