Check TrueNAS Health/Replication

Was looking for a zfs zpool health/diskspace check (SNMP), while this uses the API to check alerts.
In case there anyone else with the same req, try https://git.io/J3mvS

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Script is great, but doesn't work in its current form on this site. I found someone that re-wrote it for the current version of FreeNAS here:
https://www.ixsystems.com/community/threads/how-to-monitor-your-freenas-9-3-with-icinga-nagios-nrpe.43043/

With that version it's working perfectly.

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I am testing this against a FreeNAS system, and find that in FreeNAS versions >= 9.10.x the repl_status success string has changed to 'Up to date'

Also, the API URL seems to be hard coded to http ... so I modified mine for https. It would be good to be able to have this handled dynamically to avoid sending the root credentials in cleartext.

diff check_truenas.py.sav check_truenas.py
45c45
self._ep = 'https://%s/api/v1.0' % hostname
76c76
if repl['repl_status'] != 'Up to date'

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