frr: T6746: additional improvements after 10.2 upgrade (#4259)

* smoketest: T6746: add substring search in getFRRconfig()

Some daemons (e.g. bgpd) have several nested substrings/sections like

router bgp 100
 address-family ipv4 unicast
 ..
 exit-address-family
exit

We can now use getFRRconfig() with the substring option to extract only
 address-family ipv4 unicast
 ..
 exit-address-family

Making config validation more granular

* frrender: T6746: only re-render FRR config if config_dict did change

* frrender: T6746: fix naming glitch isis/eigrp

* frrender: T6746: add --stdout option when running with debug flags

* smoketest: T6746: remove unneeded commit_guard time

It was an invalid workarround as the underlaying issue seems to be a race
condition in CStore.

The commit process is not finished until all pending files from
VYATTA_CHANGES_ONLY_DIR are copied to VYATTA_ACTIVE_CONFIGURATION_DIR. This is
done inside libvyatta-cfg1 and the FUSE UnionFS part. On large non-interactive
commits FUSE UnionFS might not replicate the real state in time, leading to
errors when querying the working and effective configuration.

TO BE DELETED AFTER SWITCH TO IN MEMORY CONFIG

1 files changed, 2 insertions, 2 deletions

diff --git a/src/services/vyos-configd b/src/services/vyos-configd
index d558e8c26..e4655fdf7 100755
--- a/src/services/vyos-configd
+++ b/src/services/vyos-configd
@@ -335,7 +335,7 @@ if __name__ == '__main__':
                 if hasattr(config, 'frrender_cls') and res == R_SUCCESS:
                     frrender_cls = getattr(config, 'frrender_cls')
                     tmp = get_frrender_dict(config)
-                    frrender_cls.generate(tmp)
-                    frrender_cls.apply()
+                    if frrender_cls.generate(tmp):
+                        frrender_cls.apply()
         else:
             logger.critical(f'Unexpected message: {message}')