[j-nsp] Cisco IGP fast convergence

[Wayne Tucker]

On Tue, May 29, 2012 at 3:19 AM, Wan Tajuddin Wan Hussin <eazy_joe at yahoo.com
> wrote:

> We are planning to deploy MX in our all Cisco network. However, my tech
> team are not comfortable with mismatch LSA timer which MX unable to
> configure certain parameter.
>
> At the moment we are using the following setting on Cisco.
>
>
>  timers throttle spf 50 50 5000
>  timers throttle lsa 0 20 5000
>
> Has anyone deploy this type of setting and successfully integrate with
> Juniper without any issue.
>

These timers throttle SPF runs and LSA flooding.  I don't recall anything
for controlling the latter in Junos, but there are some knobs under
protocols/ospf/spf-options that accomplish results similar to the former.

That being said, you may not need to tweak anything on Junos.  The IOS
defaults tend to be conservative because they are designed for older/slower
hardware, whereas Junos was designed with the assumption that the control
plane would be separate and would have reasonable processing power
available.

If you're concerned about transient loops then loop free alternates are
better use of your resources.  They don't prevent transient loops (nothing
can), but they allow the forwarding plane to compensate for certain link
failures.

You should also look into BFD (as Doug mentioned), though that's a solution
for a different problem.

:w