02-10-2011 01:25 PM - edited 02-21-2020 05:09 PM
Hello,
We are configuring 887G router as a DMVPN Spoke device, and configure the 3G Cellular interface as backup of the ADSL interface. In our tests, we observe that if Adsl Atm0 interface is up, and we pull the ADSL cable, the Cellular interface is working properly.
But after this test, if we just reload the router, i.e. we boot the router with ADSL interface is down, we observe that without pinging the GRE tunnel endpoint the Cellular interface never comes up. After we start a single ping the tunnel destination ip everything is working properly. We think the the GRE protocol, or the NHRP protocol on the tunnel interface should trigger the Tunnel formation, but not observing as exptected.
On the 887G router there's only a static route pointing to the GRE Endpoint IP address, but instead of this host based route we give a default route, the tunnel is formed without starting a ping.
How can we make the tunnel through the Cellular interface form automatically, since this situation in some scenarios need console access to the spoke device?
We thought of a IP Sla track that would work every 10 seconds to ping the Tunnel endpoint, but this may not be the best choice,
Thanks in Advance,
Best Regards,
02-11-2011 01:46 AM
Enable tunnel keepalives.
int tun#
keepalive 1 3
HTH>
02-11-2011 04:01 AM
Hello Andrew,
Since we are using DMVPN, we thought of using gre tunnel keepalives, but the attached document specifically say that tunnel keepalive not supported if gre over ipsec is used. Does it match or is it possible that this restriction may have changed?
Thanks for your recommendation, hope it is supported,
interface Tunnel1
description Hub_Conn_To_ATM_3G
bandwidth 1000
ip address 200.200.200.1 255.255.255.0
no ip redirects
ip mtu 1436
ip nhrp authentication den123
ip nhrp map multicast dynamic
ip nhrp network-id 200000
ip nhrp holdtime 300
ip nhrp shortcut
ip nhrp redirect
ip rip advertise 5
no ip split-horizon
tunnel source GigabitEthernet0/0/3
tunnel mode gre multipoint
tunnel key 200000
tunnel protection ipsec profile dmvpnprofile shared
02-11-2011 04:12 AM
Hey - generally when I read "not supported" i take that to mean just because it says its not supported, but the command is still available in the IOS.
With that said quickly reading the basic DMVPN config, it already has something that can be used = DPD, Dead Peer Detection???
HTH>
05-12-2011 06:08 PM
Hi guys,
I am having same type of issue with 887G as Canero...
Please see the following...
I am having some strange issue with 887G router as routes drops out from routing table during idle timing.
We have configured DSL as a priority and Wireless (BGP) as secondary routes....everything works fine for few days where DSL act as a priority and Wireless as a backup, but if I check routing table after few days I always find routes for wireless is missing.
When I check logging information, it says "hold time expired" and connection dropped along with following error.
"open failed: Connection timed out; remote host not responding"
Firstly, I wonder why this has dropped eventhough it was working fine for few days. Secondly, neither cellular nor tunnels were dropped
As soon as I do "shut" and "no shut" to the cellular...everything comes back again...
Any help would be grately appreciated..
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