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What is Virtual fragmentation reassembly (VFR) and how do I know if I need it

bberry
Level 1
Level 1

I have an older 2911 router that has started reporting the following in the log. I at first though this is part of the fact that I have six T1s bonded together as I also see this in a location that also has bonded T1s. I am looking to see what this really is and if I need how do I address the message. My Multilink interface is at the bottom...

 

Aug 5 13:37:35.148 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16
Aug 5 13:38:14.460 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16
Aug 5 13:38:57.932 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16
Aug 5 13:40:12.620 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16
Aug 5 13:41:22.264 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16
Aug 5 13:42:49.956 CDT: %IP_VFR-4-FRAG_TABLE_OVERFLOW: Multilink2: the fragment table has reached its maximum threshold 16

 

interface Multilink2
description AT&T 9Mb link Circuit ID: DHEC...
bandwidth 9000
ip address #.#.#.# 255.255.255.252
ip access-group 155 out
ip nbar protocol-discovery
ip flow ingress
ip flow egress
ip virtual-reassembly in max-reassemblies 20
ip virtual-reassembly out
no peer neighbor-route
ppp chap hostname ABC123
ppp multilink
ppp multilink group 2
ppp multilink fragment disable
no cdp tlv app
service-policy output AVPN-COS

1 Reply 1

Hello,

 

as far as I recall, virtual fragmentation can be caused by e.g. NAT or PSec/GRE. Try and set the value to the highest available number, e.g.:

 

ip virtual-reassembly in max-reassemblies 1024

 

and see if that mitigates the issue...

 

 

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