In this PR the post-processing done by DANM is restructured to accomodate CNIs which do not create kernel networking interfaces.
Userpsace CNIs, or various network config CNIs all belong to this category. When such a CNI is invoked through DANM, various post-processing errors related to automatically setting certain interface specific configs (v/, DAD, IP routes etc.) in the kernel would fail simply because the interface does not exist.
These issues are universally solved by checking for the presence of a kernel interface first, and only initiating post-processing if one is found.
In this PR the post-processing done by DANM is restructured to accomodate CNIs which do not create kernel networking interfaces. Userpsace CNIs, or various network config CNIs all belong to this category. When such a CNI is invoked through DANM, various post-processing errors related to automatically setting certain interface specific configs (v/, DAD, IP routes etc.) in the kernel would fail simply because the interface does not exist.
These issues are universally solved by checking for the presence of a kernel interface first, and only initiating post-processing if one is found.