March 17, 2018

Solar Cluster: Beware, I’m ARMed

Last night, I got home, having made a detour on my way into work past Jaycar Wooloongabba to replace the faulty PSU.
It was a pretty open-and-shut case, we took it out of the box, plugged it in, and sure enough, no fan.  After the saleswoman asked the advice of a co-worker, it was confirmed that the fan should be running.
It took some digging, but they found a replacement, and so it was boxed up (in the box I supplied, they didn’t have one), and I walked out the door with PSU No. 3.
I had to go straight to work, so took the PSU with me, and that evening, I loaded it into the top box to transport home on the bicycle.
I get home, and it’s first thing on my mind.  I unlock the top box, get it out, and still decked out in my cycling gear, helmet and all (needed the headlight to see down the back of the rack anyway), I get to work.
I put the ring lugs on, plug it into the wall socket and flick the switch.
Nothing.
Toggle the switch on the front, still nothing.
Tried the other socket on the outlet, unplugging the load, still nothing.  Did the 10km trip from Milton to The Gap kill it?
Frustrated, I figure I’ll switch a light on.  Funny… no lights.
I wander into the study… sure enough, the router, modem and switch are dead as doornails.  Wander out to the MDB outside, saw the main breaker was still on, and tried hitting the test button.  Nothing.
I wander back inside, switching the bike helmet for my old hard hat, since it looks as if I’ll need the headlight a bit longer, then take a sticky beak down the road to see if anyone else is facing the same issue.
Sure enough, I look down the street, everyone’s out.
So there goes my second attempt at bootstrapping Gentoo, and my old server’s uptime.
The power did return about an hour or so later.  The PSU was fine, you don’t think of the mains being out as the cause of your problems.
I’ll re-start my build, but I’m not going to lose another build to failing power.  Nope, had enough of that for a joke.
I could have rigged up a UPS to the TS-7670, but I already have one, and it’s in the very rack where it’ll get installed anyway.  Thus, no time like the present to install it.
I’ll have to configure the switch to present the right VLANs to the TS-7670, but once I do that, it’ll be able to take over the role of routing between the management VLAN and the main network.
I didn’t want to do this in a VM because that means exposing the hosts and the VMs to the management VLAN, meaning anyone who managed to compromise a host would have direct access to the BMCs on the other nodes.
This is not a network with high bandwidth demands, and so the TS-7670 with its 100Mbps Ethernet (built into the SoC; not via USB) is an ideal machine for this task.
Having done this, all that’s left to do is to create a 2GB dual-core VM which will receive the contents of the old server, then that server can be shut down, after 8 years of good service.  I’ll keep it around for storing the on-site backups, but now I can keep it asleep and just wake it up with Wake-on-LAN when I want to make a back-up.
This should make a dint in our electricity bill!
Other changes…

  • Looks like we’ll be upgrading the solar with the addition of another 120W panel.
  • I will be hooking up my other network switches, the ADSL router and ADSL modem up to the battery bank on the cluster, just got to get some suitable cable for doing so.
  • I have no faith in this third PSU, so already, I have a MeanWell HEP-600C coming.  We’ll wire up a suicide lead to it, and that can replace the Powertech MP-3089 + Redarc BCDC1225, as the MeanWell has a remote on/off feature I can use to control it.