Router 891 CPU LIMIT vs Bandwith usage

[ahorta001]

Hi to everyone !!!

Im using Cisco routers for a while and really happy about performance and funcionalities !

What Im facing is a problem in a branchoffice that has a 891 router in the edge. This router is working fine but i think Im arriving, as grow in usage, to hardware limit. What I want to know if someone had same design usage if I need to upgrade to a better router of better series.

- WAN bandhwith 25 Mbps 

- LAN switching 60 Mbps

firwalling in LAN 

firewalling in WAN

dhcp server 

dns

nat

IPsec tunnel in WAN with 2 Mbps of traffic

QoS in WAN

15.2 is the IOS Im using 

I find this in internet that state that the 890 routers has 50 Mbps of traffic to work well 

http://www.cisco.com/web/partners/downloads/765/tools/quickreference/routerperformance.pdf

CPU usage is arriving to 90-95 % Is this ok or I can solve problem with a change of configuration? I think that IM arriving router hardware limit...

Thanks for any advice !! kind regards !!

[Joseph W. Doherty]

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Posting

For an even better look at 890 performance, see my attachment.

An 891 is undersized for you link's maximum bandwidth, but I would expect better than 2 Mbps of encrypted performance. So yes, you may have a non-optimal configuration.

Have you seen: http://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/25885-pmtud-ipfrag.html ?