Tunnel went DOWN, the fragment table has reached its maximum threshold

[JonRedn11]

Hi everyone,

Suddenly, my tunnels Cisco-Cisco stopped working and I'm getting those messages:

*Dec 15 2023 20:41:52.180: %DMVPN-5-NHRP_CACHE: Client 192.xxx.xx.xxx on Tunnel went DOWN.
*Dec 15 2023 20:42:10.352: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.102: the fragment table has reached its maximum threshold 16
*Dec 15 2023 20:42:35.201: %DMVPN-3-NHRP_ERROR: Resolution Request failed for 0.0.0.0 on Tunnel
*Dec 15 2023 20:42:41.305: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/1.300: the fragment table has reached its maximum threshold 16
*Dec 15 2023 20:43:11.329: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.102: the fragment table has reached its maximum threshold 16

I executed the command virtual-reassembly <max-reassemblies> according some comments but I still have the problem.

Please, can someone help me?

Thx

[JonRedn11]

I understand. But I have a question: Why would worked it since along time ago?

[MHM Cisco World]

This issue of ISP' not yours.

Contact them and let them check.

MHM

[JonRedn11]

In fact, I did. I'll update the case when I'll know their answers.

[MHM Cisco World]

I wish you luck friend

Update me if you can when get answer 

Have a nice weekend 

MHM

[JonRedn11]

Hi @MHM Cisco World, 

Well, the ISP told me that the problem is mine, not theirs.

I'm looking into the matter (again) and I realized the another message:

*Dec 28 2023 14:14:21.881: IKE Dispatcher: Unexpected destination port 4500. Dropping packet!
*Dec 28 2023 14:14:22.281: IKE Dispatcher: Unexpected destination port 4500. Dropping packet!
*Dec 28 2023 14:14:26.725: IKE Dispatcher: Unexpected destination port 4500. Dropping packet!

It's weird because the tunnel is UP during a certainly time and then is DOWN again.

[MHM Cisco World]

Hi friend 
can you confirm that the Hub see that the Spoke behind NAT or not ,
can you confirm that 
MHM

[JonRedn11]

Hi @MHM Cisco World happy new year!

Confirm: the Hub doesn't see the Spoke behind NAT.

[JonRedn11]

Thank you buddy. Same to you.

Happiness!

[MHM Cisco World]

*Dec 15 2023 20:41:52.180: %DMVPN-5-NHRP_CACHE: Client 192.xxx.xx.xxx on Tunnel went DOWN.
*Dec 15 2023 20:42:10.352: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.102: the fragment table has reached its maximum threshold 16
*Dec 15 2023 20:42:35.201: %DMVPN-3-NHRP_ERROR: Resolution Request failed for 0.0.0.0 on Tunnel
*Dec 15 2023 20:42:41.305: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/1.300: the fragment table has reached its maximum threshold 16
*Dec 15 2023 20:43:11.329: %IP_VFR-4-FRAG_TABLE_OVERFLOW: GigabitEthernet0/0.102: the fragment table has reached its maximum threshold 16

Solution is Using MTU less than what you get from Ping (df bit set) with at least 40 bytes

*Dec 20 2023 21:06:29.268: NHRP: MACADDR: if_in INTERFACE netid-in 0 if_out Tunnel0 netid-out ID
*Dec 20 2023 21:06:29.268: NHRP: Checking for delayed event 0.0.0.0/CLIENT_VPN on list (Tunnel0).
*Dec 20 2023 21:06:29.268: NHRP: No node found.

the solution for this is run CEF in router