High CPU Utilization on 1335 when using GRE over VPN

[Anonymous]

     Any ideas what the limitations are on number of  GRE over VPN tunnels a 1335 can support.  I am currently doing about 9 with OSPF on the GRE  tunnels and the processor runs at about 80% utilization and the process that is consuming the most is packet routing process at about 50-60% of the processing power.

[Anonymous · Accepted solution]

OSPF, GRE, and IPSEC are all processor-intensive functions and when combined they're even worse. Unfortunately there are no hard and fast rules about this sort of thing, since everyone's network will be different. We have no way of testing all the various scenario's, so we end up with some generalities.

Given what you've described I would generally say to stop at 5 GRE w/IPSEC tunnels and OSPF in a 1335, in order to leave some headroom in the CPU for spikes of activity. Going up to 9-15  tunnels like that you would want a unit with a more robust processor, perhaps a NetVanta 3430 but even then I wouldn't exceed 15 in that unit.

Regards,

Ronnie Colvin

Adtran Applications Engineering

[Anonymous]

So what would be the suggested router to accomplish up to 10 connections and have room for 20 total.  Would a 4430 be able to handle this.

[Anonymous]

For growth up to 20 GRE w/IPSEC and OSPF, I would definitely recommend the 4430. It would be the only one with the horsepower to deal with the encryption and the OSPF with GRE and still be able to do everything else it needs to do (I'm guessing there's firewall going on, possibly QoS/traffic shaping, etc)

[Anonymous]

We are doing VOIP across so yes QOS and traffic shaping.

[Anonymous]

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Thanks,

Levi