Why is packet fragmented even if DF bit is set after R5.2.2?

Summary

Packet is fragmented even if DF bit is set.

Question

Why is packet fragmented even if DF bit is set after R5.2.2?

Customer Environment

SZ124 R5.2.2

Resolution

Packet handling with DF bit set and over MTU size through Tunnel is configured by the following flags.

------ TUNNELMGR Information ------
tunnelmgr Service:      Enabled
Tunnel Establishment:   Disabled
Tunnel IPSec:           Disabled
Tunnel Authentication:  Enabled
Tunnel Cipher:          Disabled
Tunnel Cipher Key Len:
Tunnel Forward Bcast:   Disabled
PMTU:                   Auto
PMTU Discovery:         Disabled
Node Affinity:          Disabled
Force Fragmentation:    Disabled
Offload:                Disabled
Dual Tunnels:           Disabled

Packet handling condition was changed after R5.2.2 as below
DFFF PMTU disc(packet > MTU)
not setdisableddisabledfragment
not setdisabledenabledfragment
not setenableddisabledfragment
not setenabledenabledfragment
setdisableddisabledfragment
setdisabledenabledicmp error + packet drop
setenableddisabledfragment
setenabledenabledfragment

However, Ruckus discussed this function again and rolled back to same behavior as R5.2.1 as below.
DFFF PMTU disc(packet > MTU)
not setdisableddisabledfragment
not setdisabledenabledfragment
not setenableddisabledfragment
not setenabledenabledfragment
setdisableddisabledicmp error + packet drop
setdisabledenabledicmp error + packet drop
setenableddisabledfragment
setenabledenabledfragment

This change was made in ER-11149 after R5.2.2 and R6.1.

Article Number:
000012253

Updated:
June 05, 2022 06:09 PM (8 months ago)

Tags:
Configuration, Troubleshooting, Known Issues and Workarounds, SmartCell Gateway

Votes:
1

This article is:
helpful
not helpful

Working...Please wait

This is here to prevent you from accidentally submitting twice.

The page will automatically refresh.