Simple question....

How do I NOT torch my router when I want to transfer large files between two subnets if I am routing on a stick?

I did a quick 5 sec test and my router was at 95% transferring a large file between 2 different subnets through one single "on a stick" gig port. I already knew it would be high and not to do this but I wanted to see processor usage.

Would a layer 3 switch give me line speed subnet to different subnet transfers over a full gigabit network? Of course on a layer 3 switch I could use different physical ports and not be on a stick. Would this kind of transfer torch the cpu in the switch? i.e. say ... like a 3750E which has a powerhouse 160GB/s forwarding speed?

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Awesomesauce!!!!

I went ahead and set the speed to 100meg forced. I notice that at a 100Mbps transfer the CPU usage topped at 45%.

There is no real purpose to this. I am doing this stuff simply to learn. I want to test the limits of what you can do while routing to the internet as well as between subnets while your routing is on a stick. I am thinking that a true gig layer 3 switch can forward between ports on different subnets at line speed. I am just looking for confirmation before asking to borrow one from some folks I know to learn on and play with for a little while.

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Awesomesauce!!!!

Depending on the platform you have take a look at the router performance pdf (http://www.cisco.com/web/partners/downl ... rmance.pdf) and see what it is rated for, that number doesnt matter whether it is inside to outside or just between subnets on the same router, as they are all doing basically the same thing (a L2/L3 packet rewrite).

Bare in mind with the numbers in that PDF though that they are tested using pretty small packet sizes.

And your query regarding the L3 switch, yes you will be able to a LOT faster transfers using a L3 switch as the gateway between the two different subnets.

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David
CCIE R&S #38338, CCIP, CCNP

http://networkbroadcast.co.uk - My Blog
http://twitter.com/davidrothera

Thank you very much. I have reviewed that document you linked. I have a 1921 that we are talking about here so it is either the same as or extremely close to the 1941. 1921 isn't listed so I have to assume for now that the router can forward 299,000pps. Doesn't cisco test at 64k packet sizes?

At any rate I may still ask to borrow a friends 3750e gig switch to do some testing and learning on. I sincerely appreciate your confirmation on the l3 switching question I have. I also appreciate you clearing up the limit of what the router can address is on both interfaces combined, one single interface, or a combination as a global max in performance. I believe the only way at this point to keep cpu usage below an acceptable (where I feel safe) 75% is to cap the interface speed at 100 or as you have confirmed use a l3 switch.

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Awesomesauce!!!!

Get a better router or get an L3 switch.

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http://blog.alwaysthenetwork.com

Vito no matter how I feel that day your advice is always full of happy emotions and is well received lol

........No need to. This router is perfectly fine and is actually faster than anything in it's class prior to this one.

I'll borrow a layer 3 gig switch from my good friend who is a JNCIE and is slowly selling his Cisco gear off to replace with Juniper. He refuses to help me with Cisco because he learned the hardway on his own and insist I do as well. He has a great point though. I can probably trade him my wife's dog for his switch lol. Little yapper she is (dog, not wife).

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Awesomesauce!!!!