[SWEET-6] Restart scenario

[vvalderrv]

Use VOM to handle sweetcomb restart managent.

• VPP restart
• • sweetcomb must detect the vpp if it's down (sr_plugin_health_check_cb - already implement)
  • sweetcomb should wait to vpp until it be restart (third part should restart it, like systemd)
    • sweetcomb should print INFO message to log, the vpp is down
  • sweetcomb (VOM) should create interfaces (host, loopback, ...)
  • need create (cope from honeycomb) YANG modules for vpp interfaces
  • use VOM (OM::replay) to reconfigure VPP
  • The sweetcombshould return error message when the VPP is down and agent want configure VPP
• Sweetcomb is restart
  • OM::populate
  • download all the configuration from VPP
  • sweetcomb store running datastore to file
  • create backup of running datastore
  • must handle possible situation when the backup is broken
    • have copy of the older version of the backup?
  • when the sweetcomb is correct stop this backup should be remove
  • backup should be create after every change
  • when the sweetcomb is restart from crash

• • • it's look for the backup

• • • • restart sysrepo running config from backup
      • "reset" it's running config to VPP