Compatibility
Kunai has been built to be compatible with all the Linux LTS kernels(from 5.4 to 6.6 at the time of writing). Compatibility is tested in our CI/CD pipeline at every modification to guarantee stability.
Even with this rigorous testing it is possible that the program crashes before it can even start monitoring. If that happens to you do not panic, it does not mean the tool is bad, it just means your kernel is not supported yet, for a reason or another. Having a single binary fitting to several kernels is great for deployment however this has a cost: the programs needs to be aware of some of the changes made between the kernel versions.
If you are interested into getting more knowledge about how kunai makes to supports several kernels at once, you should take a read to the BPF CO-RE reference
In order to get your kernel version, run the following command uname -r, then you can check the following table.
| OS | Kernels |
|---|---|
| Ubuntu-20.04 | 5.4 |
| Ubuntu-22.04 | 5.15 |
| Archlinux | 5.18 to 6.6 |
If your kernel version:
- is between the minimum and maximum kernel version, there are chances it will work without issue
- is higher than the maximum version supported, cross your fingers, it might work
- is lower than the minimum version, it is likely it will fail at running but try anyway you have nothing to lose
Please let us know if you tested kunai with success on an OS/kernel not listed above.
Let us know so that we can update the table
Known issues
RLIMIT_MEMLOCK
Sometimes (mostly happening on old kernels) Kunai may fail at loading with the following message (or something very similar).
[2024-04-11T13:25:35Z WARN aya::maps] RLIMIT_MEMLOCK value is 8 MiB, not RLIM_INFINITY; if experiencing
problems with creating maps, try raising RLIMIT_MEMLOCK either to RLIM_INFINITY or to a higher value
sufficient for the size of your maps
Error: map error: failed to create map `FN_DEPTH` with code -1
Caused by:
0: failed to create map `FN_DEPTH` with code -1
1: Operation not permitted (os error 1)
You can check the current RLIMIT_MEMLOCK with ulimit -l and set the limit temporarily with
ulimit -l unlimited
You can increase the limit for root user permanently in /etc/security/limits.conf
# increase root user memlock
root hard memlock infinity
root soft memlock infinity
For more information man limits.conf