Corona sends SNMP queries to defined CIDR ranges and populates SQL database based on nodes found. Some particular problems it tries to deal with:

• Only discover one node once
• To that effect it has priority list of idDescr lo0.0, loopback0, vlan2 etc. Higher priority will always replace lower priority interface (say you have MGMT in loop0 but giga0/2.42 has valid MGMT address towards L2 metro)
• Tries to handle gracefully renumbering, renaming, etc

1. gem install corona
2. corona
3. ^C (break it)
4. edit ~/.config/corona/config
5. put corona in crontab as corona|mail -E -s 'new nodes found' foo@example.com

• You need to configure SNMP community
• You need to define CIDR to poll and CIDRs to ignore (subset of those you poll)
• CIDR in example config is list, but can be replaced with 'string' which points to file, where CIDRs are listed

[fisakytt@lan-login1 ~/projects/corona]% corona --help
Usage: corona [options] [argument]
    -d, --debug           Debugging on
    -p, --poll            Poll CIDR [argument]
    -r, --remove          Remove [argument] from DB
    -m, --max-delete      Maximum number to delete, default 1
    -o, --purge-old       Remove records order than [argument] days
    -s, --simulate        Simulate, do not change DB
    -h, --help            Display this help message.

% corona -p 192.0.2.0/28   # poll specific CIDR
% corona -r core-sw1       # remove specific record
% corona -o 7              # remore records older than 7 days