GRE Tunnel capacity

[faditak85]

Dears ,

im sicking an exact information about the GRE tunnel capability from capacity point of view as i'm wondering about the maximum BW a GRE tunnel can support ( of course by using the correct hardware to support that )

can we send up to 2 G or  more over a  GRE tunnel without having any issue or limitation ? 

Thanks in advance

Fadi

[marce1000]

 - Check if this thread can be helpful :

          https://community.cisco.com/t5/routing/gre-tunnel-max-bandwidth/td-p/1400841

 M.

[faditak85]

Hi MArce,

thanks but i have already checked it and it doesn't help , as i need more global concrete information about the GRE tunnel capabilities whatever the Hardware / software in use.

cheers

[Georg Pauwen]

Hello,

in general, there is no limit to how much traffic a GRE (not IPSec) tunnel can carry, other than what limits the device has in terms of memory and CPU. And obviously the bandwidth of the link is a limiting factor as well.

[faditak85]

Thanks George !

[Joseph W. Doherty]

As noted by others, it really depends on the device.

In the past, I've used an IPv4 GRE tunnel, on a 6500 with a sup720, to pass IPv4 and IPv6 traffic at gig rate (duplex) w/o issue. I also tried, on same platform, using a IPv6 GRE tunnel, which folded under load with very low traffic volume. (It turned out, the IPv6 GRE tunnel was only supported in hardware starting with the sup2T.)

One "gotcha", that can often make or break GRE tunnel performance, is whether tunnel traffic needs to be fragmented.

[Richard Burts]

I agree with @Georg Pauwen and @Joseph W. Doherty that the capacity for GRE is very much dependent on the platform on which you will process the GRE tunnel. I can think of a couple of factors that may be specific to GRE:

- can this platform process GRE in hardware or other enhanced processing or will it need to process the GRE using CPU?

- since GRE does add some data to the packet fragmentation may be an issue

Other than those aspects I would expect that the capacity of just about any platform to send GRE traffic is the same as its capacity to send other IP traffic.

[Deepak Kumar · Accepted solution]

Hi,

I agree with @Richard Burts It depends on the platform you used. For more information, you can check the device datasheet and performs test reports. Which are avaiable on Cisco websites or google it.

[faditak85]

Thank you Guys for your help 

cheers