Bug 199745

Summary: netem queue does not accept 0.0% for loss or duplicate
Product: Networking Reporter: Stuart Marsden (stuartmarsden)
Component: OtherAssignee: Stephen Hemminger (stephen)
Status: RESOLVED CODE_FIX    
Severity: normal    
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: any Subsystem:
Regression: No Bisected commit-id:

Description Stuart Marsden 2018-05-17 09:03:05 UTC
https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/commit?id=927e3cfb52b58fbdf217d84204d653db101c137a


This commit changed how percentages in to netem were parsed.

A percentage of 0.0% now raises an error. This may make sense in the context of the commit but it also applies to loss and duplicate. In that context 0.0% is a valid entry and one that has worked before. This therefore breaks userspace applications such as the CORE Emulator.

As an example this command gives an error 
>"tc qdisc replace dev veth2.0.34 root handle 10: netem delay 120000us 0us 25%
>loss 0.0% duplicate 0.0%" 

when it should be valid and used to work prior to the referenced commit.
Comment 1 Stephen Hemminger 2018-05-17 23:33:09 UTC
Patch submitted for next version:
https://patchwork.ozlabs.org/patch/915857/