Arch Linux

xExekut3x

Member

Registered: 2014-09-12

Posts: 8

Customer Kernel Flag Help

I've followed this - https://wiki.archlinux.org/index.php/Ke … ild_System - up to renaming pkbase. At a loss as to where add a custom kernel flag.

Trying to get 'tc' to work correctly so I can simulate packet loss on this test device.

Receive

Error: Qdisc not found. To create specify NLM_F_CREATE flag

when I try and run

sudo tc qdisc change dev eth0 root netem loss 0.3%

Looked up the error and everything pointed to adding the "NLM_F_CREATE" to a custom kernel build.

So where do I add that flag?

Slithery

Administrator

From: Norfolk, UK

Registered: 2013-12-01

Posts: 5,776

Re: Customer Kernel Flag Help

https://wiki.archlinux.org/index.php/Ke … pare.28.29

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No, it didn't "fix" anything. It just shifted the brokeness one space to the right. - jasonwryan
Closing -- for deletion; Banning -- for muppetry. - jasonwryan

aur - dotfiles

loqs

Member

Registered: 2014-03-06

Posts: 18,786

Re: Customer Kernel Flag Help

@Slithery it is not a kernel config option where in the source are you suggesting should be changed and what to?
Edit:
@xExekut3x see https://git.kernel.org/pub/scm/network/ … isc.c#n417 you appear to need to use tc add or tc replace for such an operation not tc change.

Last edited by loqs (2018-06-22 14:54:12)

Slithery

Administrator

From: Norfolk, UK

Registered: 2013-12-01

Posts: 5,776

Re: Customer Kernel Flag Help

Sorry, I thought it was a kernel config option.

---

No, it didn't "fix" anything. It just shifted the brokeness one space to the right. - jasonwryan
Closing -- for deletion; Banning -- for muppetry. - jasonwryan

aur - dotfiles

xExekut3x

Member

Registered: 2014-09-12

Posts: 8

Re: Customer Kernel Flag Help

@loqs

I'm running a RPM test from a Juniper switch. https://www.juniper.net/documentation/e … rview.html

replace doesn't throw any errors, but I'm also not seeing any packet loss from the test.

add throws the error - Error: Exclusivity flag on, cannot modify.

I bumped the % up to 5%, but still no packet loss.

Is - sudo tc qdisc replace dev eno2 root netem loss 5% - not the right command here?

EDIT: Nevermind! Seeing packet loss! YAY! Thanks a lot!
EDIT: Scratch that. Might have been a fluke. Who knows. Packet loss was showing 50% from the test. Had to have been a fluke.

Last edited by xExekut3x (2018-06-22 15:18:32)