Snapmirror

Well, I recently had the pleasant task of implementing SnapVault backups, that are being shipped to an offsite location with SnapMirror. That in itself isn’t the bad thing, however we decided against Protection Manager (since it was a charged product back when we decided on this). So I basically had the three tasks: Actually implement the SnapVault stuff (and learn my way around it and also document it) Write a bunch of scripts, that help us in creating scheduled backups of our databases Create a monitoring script, that’ll fit into our Nagios environment already in place Well, two months later (sadly it still has some kinks - I can’t figure out this one bug though for the life of it) and a few hundred hours of working on/with it and out came four things: ...

As I wrote before, we have a bunch of filers (and a ton of volumes w/ luns on them), that I need to monitor. At first, I tried the existing NetApp Nagios-Plugin(s), but they all use SNMP and with that I can either watch all volumes or none. And that didn’t satisfy me. Don’t get me wrong, the existing plugins are okay and I still use them for stuff (like GLOBALSTATUS or FAN/CPU/POWER) which isn’t present in the API or real hard to get at, however I wanted more. So I ended up looking at the NetApp API, and ended up writing a “short” plugin for Nagios using Perl. Maybe if I’m ever bored, I’ll rewrite it using C, but for now the Perl plugin has to suffice. So far the plugin supports the following things: Monitoring FlexVolumes (simply watching the free space) Monitoring LUN space (the allocated space inside a FlexVolume for iSCSI/FC LUNs) Monitoring Snapshot space (the allocated space inside a FlexVolume for Snapshots) Monitoring SnapVault relations (and their age) Monitoring SnapMirror relations (and their age) The plugin will return performance data for most (if not all) of those classes. It needs a user on the filer you wish to monitor - which sadly needs to have the admin role.

After figuring out the SnapVault stuff, I needed to implement a whole bunch of SnapMirror relations. As I am lazy (as in click-lazy), I ended up writing a somewhat short Bash script, that’ll either establish a bunch of SnapMirror relations (for a single host) or just for a single volume. The script expects, that SSH public key authentification has been set up, and that the source for the SnapMirror exists and is online/not-restricted.

Well, we’ve been trying to come up with a decent way to backup NetApp snapshots to tape (SnapMirror To Tape), so we evaluated all the available methods of using NDMP backups. There’s Image Backup in two different variants - FULL and DIFFerntial There’s SnapMirror To Tape So the Image Backup is one of the ways. However the DIFFerntial backup only works for CIFS and NFS shares (which we don’t use). We only have FC luns (or rather FCoE luns), so there’s only a single (or in case of the boot luns more than one) file in each volume. With that however, each run of the Image Backup with the DIFFerential option, it’s gonna backup the full size of the volume (plus the deduplicated amount). ...