Add overrides for Synology MIB

[koraktor]

This adds overrides for the Synology MIB to increase usefulness of the prodived metrics.

Human-readable strings are now provided as DisplayString values. The metrics raidFreeSize and raidTotalSize are now gauges.

[brian-brazil]

Can you regenerate snmp.yml with the latest MIBs?

[brian-brazil]

CI is still failing, make sure you have the latest mibs.

[koraktor]

@brian-brazil Done.

But apparently there were a few unrelated changes that were caused by make clean mibs and now caused the generator tests to fail

[brian-brazil]

Hmm, are you sure the generator is built from the latest head?

[koraktor]

Yes, latest commit (before mine) is 1b3b053.

[brian-brazil]

The only diff I'm seeing on head is for 300: cpri. By any chance are you on OSX? I've seen weirdness with netsnmp there.

[koraktor]

Ok, that’s the problem. I can rebuild snmp.yml on a Linux system eventually, but it might take some time.

[SuperQ]

The cpri is new in the latest MIB (we don't version pin this MIB). #557

[SuperQ]

Ok, @koraktor, please rebase against head, that should fix up the unrelated diff.

[koraktor]

Still failing because of the missing fixed_size: 6 lines. Probably the macOS problem?

[SuperQ]

That could be macos related. Depends on what version of net-snmp you've compiled against.

[koraktor]

Building on Ubuntu results in the same file. Both Ubuntu and macOS use newer versions of Net-SNMP (5.8 and 5.9) than the Circle CI build (5.7).

[SuperQ]

I'm on Ubuntu 20.04/net-snmp 5.8. A freshly built generator doesn't drop the fixed_size: 6.

You could try using the Docker generator instructions, then it would match what's in CI.

[koraktor]

I thought it wouldn’t be worth the hassle to fix the build for a text file that can be cleaned up manually. So I did that for the fixed_size: 6 lines.

Now there’s one last problem:
The override for the serialNumber is not applied in the CircleCI build.

[brian-brazil]

Hmm, that's odd. It works for me locally too.

[koraktor]

Rebased on master, still failing on CircleCI.

[koraktor]

Rebased on master again.
Looks like the tests finally succeed now.

Any chance to get this merged now? @brian-brazil @SuperQ

[brian-brazil]

Thanks!