using managed switches, instead of layer2 switches for storage network?

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SilverNodashi

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Hi,

We only use layer2 gigabit switches and I'm considering "downgrading" to (smart / web?) managed switches instead. They generally cost about 1/3 - 1/4 of Layer2 switches and provide most of the same features of Layer2 switches.

Can anyone, who has some experience (with problems / performance degradation / tuning / etc) give me some insight on using managed switches instead of Layer2 switches for a storage area network? The storage area network has some NAS, and some SAN devices, all of which either has 4 or 8 GBe NIC's and use Load Balance / Link Aggregation - with the web smart switches support as well.

We don't use jumbo frames, or VLAN's (but I'm considering using VLAN's as well).

the only real downside that I can think of is redundant power supplies. BUT, for the price of one Layer2, I can get 4 web smart switches from the same supplier, which effectively means I could have better redundancy with 2 switches backing each other up. Our network is not setup with Trunking either.
 
You've got me confused now. I always thought that most "Web or Smart" switches is actually L2. L3 is always where the cost implications hits hard me thinks? I cant think of any newish switches that does not support Jumbo Frames, qos, vlans etc.
 
packetloss said:
You've got me confused now. I always thought that most "Web or Smart" switches is actually L2. L3 is always where the cost implications hits hard me thinks? I cant think of any newish switches that does not support Jumbo Frames, qos, vlans etc.
Click to expand...

That's what's confusing me as well. Layer3 is routing. It has all the Layer2 features as well, but is slightly slower due to the routing and also more costly.
Web Smart switches doesn't support all the layer2 features, like stacking / redundant PSU's, SMON, RMON, SMNPv3 and a few other protocols. I don't need any of those features, but what I don't know is it it will take a performance hit or not. And the sales reps at any supplier won't really give me answers based on usage experience, but rather on sales targets :)
 
I think you are confusing Management with Layer 3.

You can have management on a Layer 2 switch, Cisco 2924 as an example.
The management part gives you access to the switch via an IP address and allows you to do global & port based configurations, so you can set speed, duplex, vlans, QoS etc etc and at the same time allow you to manage the switch via IP/SNMP with OpenView, CiscoWorks etc etc. Dumb Layer 2 switches don't offer you all these features, it's basically plug and go.

Layer 3 on the other hand gives you routing functionality so essentially you have a router & a switch in the same box, they usually cost a lot more. A Layer 3 switch is not necessarily slower than a Layer two switch as the switching fabric is still implemented in ASICs with a connection to the routing engine for traffic that needs to get outside the switch or vlans. So it's pretty much the same in theory as connecting a external router. Obviously when you are going to do fancy level 3 traffic manipulation things are going to slow down a tad as the method of operation is different.

If your needs are for SAN look at gear specifically designed for it.
http://www.cisco.com/en/US/products/hw/ps4159/index.html
http://www.cisco.com/en/US/products/ps9441/Products_Sub_Category_Home.html
 
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ponder said:
I think you are confusing Management with Layer 3.

You can have management on a Layer 2 switch, Cisco 2924 as an example.
The management part gives you access to the switch via an IP address and allows you to do global & port based configurations, so you can set speed, duplex, vlans, QoS etc etc and at the same time allow you to manage the switch via IP/SNMP with OpenView, CiscoWorks etc etc. Dumb Layer 2 switches don't offer you all these features, it's basically plug and go.

Layer 3 on the other hand gives you routing functionality so essentially you have a router & a switch in the same box, they usually cost a lot more. A Layer 3 switch is not necessarily slower than a Layer two switch as the switching fabric is still implemented in ASICs with a connection to the routing engine for traffic that needs to get outside the switch or vlans. So it's pretty much the same in theory as connecting a external router. Obviously when you are going to do fancy level 3 traffic manipulation things are going to slow down a tad as the method of operation is different.

If your needs are for SAN look at gear specifically designed for it.
http://www.cisco.com/en/US/products/hw/ps4159/index.html
http://www.cisco.com/en/US/products/ps9441/Products_Sub_Category_Home.html
Click to expand...

Not at all.


Web smart / managed switches is a step below Layer 2 :)

Managed, Layer 2, Layer 3 (routing) and Layer 7 (firewalling / packet filter) all have web interfaces.
But, managed switches doesn't have RMON /SMON / redundant power supplies


See here:

Managed: http://www.duxbury.co.za/Netgear/da...abit_ethernet_10_100_1000/GS724TP_GS748TP.pdf
Layer 2: http://www.duxbury.co.za/Netgear/da...ernet_10_100_1000/GSM7212_GSM7224_GSM7248.pdf


The price different between those 2 is about R5K, which means I could buy 3 managed switches for the same price as one Layer 2 switch.
 
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like ponder said. All switches are layer 2 devices. reference the ISO model for more information.
Switches can move data from one point to another. layer 2 (data link layer). Whereas routers can route data from one network or interface to another, layer 3 ( network layer).

Now a days you do get layer 3 switches that can do limited routing, is that what you are talking about?
 
As I said before,

The one switch does PoE, the other does basic routing ----> hence the price difference, I don't think you need the PoE from your previous post, do you need a switch capable of Layer 3?

At those prices you can rather look at a decent HP switch :)
 
guys, never mind. I can see this is above your knowledge.


Why on earth would we spend R400K on a Layer 7 switch, and R14K on a Layer2 switch is all hubs and switches are the same? If you can figure that one out, then please tell me.


I'm not talking about your crappy cnet hub that you got from the PC-shop down the road.....
 
SoftDux-Rudi said:
guys, never mind. I can see this is above your knowledge.


Why on earth would we spend R400K on a Layer 7 switch, and R14K on a Layer2 switch is all hubs and switches are the same? If you can figure that one out, then please tell me.


I'm not talking about your crappy cnet hub that you got from the PC-shop down the road.....
Click to expand...


When you mouth off like that then you are the only one appearing to have a lack of knowledge. I suggest you figure it out yourself if you are so knowledgeable seeing we are the idiots.

Nobody said they are the same but then again that comes from you not understanding.
 
You obviously lack the capacity to read.

so please read my post and you will see clearly what the difference is between the two switches.

If you do not know the difference between a HUB and a SWITCH then good luck.

Please read before you go at everyone like that.

PS. reading over your original post it appears you have a serious shortage of understanding when it comes to networking.
 
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Explain this one to me:

NoLogic001 said:
like ponder said. All switches are layer 2 devices. reference the ISO model for more information.
Switches can move data from one point to another. layer 2 (data link layer). Whereas routers can route data from one network or interface to another, layer 3 ( network layer).
Click to expand...


And yes, I agree all switches run on the the OSI layer2 level. BUT, all switches don't have the same features. A layer 3 switch has extra features which a layer 2 doesn't have. Similarly, a layer 2 has extra features which a managed switch doesn't have.

But, I seriously doubt manufacturers have labeled Layer.


Have you worked with Layers2, Layer3 and layer7 switches? And I'm not talking about plugging in a cable and setting up an IP on a client's PC. I'm talking about extensively worked on it.
 
Actually yes, hence the ccnp. But thats another discussion

So I will step out from this thread as it is getting know where, if you need help pm me, and there is an hourly rate involed. Good Luck and good Googling.
 
well, seeing as you know everything, explain this to me.

What's the difference between these 2 switches:

Smart Switch:
http://www.jump.co.za/products/details/11105-netgear-gs724ts-prosafe-24-port-gigabit.htm
http://www.jump.co.za/products/prices/51356875-netgear-24-port-smart-switch-2.htm - even cheaper

Layer2 Switch:
http://www.jump.co.za/products/details/6211969-netgear-gsm7224-24-port-layer-2.htm



The thing I'm trying to get to, what exactly is the differences, if you say they're all layer2?




Here's also a list, from D-Link:


Smart switches:
http://d-link.co.za/gr.php


Layer2 switches:
http://d-link.co.za/gigabitl2m.php
 
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Does the design, implementation and management of a 5000 user campus network using redundant Cisco 6509 in the core & distribution across several buildings with 5509 & 5505 floor switches and a 20 rack server room qualify one to comment here?
 
ponder, maybe Cisco doesn't class their switches differently like D-Link / NetGear / HP, etc which might be why you don't understand what am I talking about? I never said you don't know anything. But you seem to judge me as not knowing anything because I ask this question?

Can you tell me the differences between those 2 devices? That's all I want to know. I know OSI, I know where a hub, switch and router fits in. BUT, that doesn't tell me why one layer 2 switch (which the manufacturers class as a smart switch, instead of a layer 2 switch) costs 3x more than another layer2 switch. That's what I need to know.
 
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