Running ping with kron

I'm using SAA generated traffic for such purpose at one customer and BGP at other customer (just for keeping the tunnel UP not really for routing).

Thanks for the information. Though, I am carefully trying to master the actual traffic volume for costs purposes, the SAA traffic might be expensive... The VPN tunnel is the fallback circuit for a SCADA application, the Internet access is a GPRS link, that I want to monitor 24H/24 within the data budget (i.e. 50 MByte/month). It cannot afford any blabbering, unless the "keepalive" timers are fully settable.

To be tested then... Any other idea ?

Thanks

Patrick

"Ivan Ostres" a écrit dans le message de news: snipped-for-privacy@news.individual.net...

Apparently not. Even though "ping a.b.c.d" requires precisely 0 interaction, the ping command *CAN* be interactive, "ping ip", and kron is really fussy about it.

Right, that is true that "ping" can be interactive, too bad it is classified in this list for my purpose... Also, I've seen in the reference that "ping" can be cancelled by some key sequence, I don't remember what sequence. This could also be a reason why "ping" is forbidden in the kron cli list...

Would any other cli command allow to specify the source IP address (or interface) ? That would also do the job in triggering the VPN tunnel (according that this cli command is not interactive)...

Regards,

Patrick

"Mart>

Hi,

I once saw someone use NTP on a cisco pointing to an arbitrary, but selected, address to bring up something or other.

Don't know if you can do real NTP at the same time as this 'fake' ntp or not.

Must be other options too:-

ospf with fake, or real, neighbours? tunnels ...

I've always used BGP when I've needed a router to generate continuous traffic. You can specify the source and destination address desired, and even if you don't configure a peer at the other end, you will still get retries on the initial TCP connection setup. If you do have a peer at the other end, you have full control over how often a keepalive will be sent. Use for routing purposes is optional.

Good luck and have fun!

-----------------------------------------------------------------------------------------

------------------------------------------------------------------------------------------

Could RTR be useful?

I would keep up a tunnel and I set up a RTR section with ping command every 1 minute. It did work.

rtr 1 type echo protocol ipIcmpEcho timeout 500 frequency 60 rtr schedule 1 start-time now

Alex.

Hi all,

Yup, it is indeed !

This SAA thing is just perfect for my purpose, one can even set the "source-ipaddress" of the VPN interface in the echo command ! The debug ip packet shows the only 64 bytes of the icmp packet going out every minute, no blabbering, just pure efficiency...

Actually, this features turns the low-cost dynamic-IP-address-based Internet connections into reliable always-on links to the remote sites, with static VPN IP addresses ! Whatever the status of the computers at the remote sites, the centralization site can monitor the links and have access to the VPN remote routers.

BTW do you have the GPRS service from the cellular networks over there in the US ?

Thanks a lot Alex, I have been looking forward to finding a cisco internal solution for a couple of months...

Best regards,

Patrick

FYI, I added the "life forever" parameter in the rtr schedule and it now works forever.

Thanks Ivan for pointing out the SAA issue and Alex for providing the rtr example.

Best regards to all,

Patrick :-)

"Patrick A" a écrit dans le message de news: