* Add `bridge_network_hairpin_mode` client config setting
* Add node attribute: `nomad.bridge.hairpin_mode`
* Changed format string to use `%q` to escape user provided data
* Add test to validate template JSON for developer safety
Co-authored-by: Daniel Bennett <dbennett@hashicorp.com>
In Nomad v0.12.0, the client added additional fingerprinting around the
presense of the bridge kernel module. The fingerprinter only checked in
`/proc/modules` which is a list of loaded modules. In some cases, the
bridge kernel module is builtin rather than dynamically loaded. The fix
for that case is in #8721. However we were still missing the case where
the bridge module is dynamically loaded, but not yet loaded during the
startup of the Nomad agent. In this case the fingerprinter would believe
the bridge module was unavailable when really it gets loaded on demand.
This PR now has the fingerprinter scan the kernel module dependency file,
which will contain an entry for the bridge module even if it is not yet
loaded.
In summary, the client now looks for the bridge kernel module in
- /proc/modules
- /lib/modules/<kernel>/modules.builtin
- /lib/modules/<kernel>/modules.dep
Closes#8423
