“We’re putting the band back together.”

Five o’clock. Time to shut down the ol’ laptop and go watch some TV. Or not. I feel the urge to create again. I have a bunch of hardware laying around that’s gathering dust, and it’s time to assemble it into something I can use to learn and share.

I’m not looking for anything flashy here. Money is tight and the future is uncertain for me and millions of others, so while I’d love a few old Dell servers or some shiny new NUCs, I’m sure I can cobble together something useful out of my closet for free. Initially I was going to put together a single machine and set up nested virtualization, but my best available equipment only has four cores and frankly, I feel like it’s cheating anyway. I’m a hardware junkie, so I cobble.

With a day’s work, I have scraped together a cluster of machines. One is from my original homelab build: a Dell Optiplex 9010 motherboard and i5 processor bought off eBay and transplanted into a slim desktop case. It has four DIMM slots, so it’s going to be one of my ESXi hosts. The other VM host is a Dell Optiplex 3020 SFF i5 desktop. Alas, it only has two DIMM slots, so it maxes out at 16GB with the sticks I have. I also manage scrape together a third system with eight gigs of RAM and a lowly Core 2 Duo. Transplanted into a Dell XPS tower case formerly occupied by a Lynnfield i7, it has enough drive bays that I can drop in a one terabyte SATA SSD and three 800GB SAS SSDs in RAID-0 on an LSI HBA. This system takes the role of an NFS-based NAS running on CentOS 8 and has no problems saturating a gigabit link.

It’s not all roses–my networking is all gigabit–but it totals eight cores, 48GB of usable RAM and over 3TB of flash storage. A few hours after that, I have a two-node ESXi 6.7 cluster configured and vCenter showing all green. I toyed briefly with installing 7.0, but I want to give that a little more time to bake, and besides, if what I’m planning doesn’t directly translate then I’ve done something wrong.

What are my goals here? Well, I want to work on a “let’s automate VMware” series. Not satisfied with the kind of janky scripts I’ve cobbled together to automate some of my uglier processes, I want to learn how to do this the right way. That certainly means Terraform, some kind of configuration management (Ansible, Salt, Puppet, Chef or a combination), building deployment images with Packer, and figuring out how to safely do all of this with code that I’m storing in Github. Possible future projects might involve integrating with ServiceNow, Splunk, monitoring (Zabbix, Solarwinds) or other business tools, and using the resulting tooling to deploy resources into AWS, Azure, DigitalOcean and/or VMware Cloud.

Why do this on my own? While I do have the resources at work, I feel more comfortable doing this on my own time and at my own pace. Plus, by using personal time and resources, I feel safer sharing my findings publicly with others. While my employer has never given me any indication that it would be an issue, I’d just rather be able to do and refine my skills on my own time.

So stay tuned; there’s more content to come from the homelab!

It was early 2005.  My Southern California commute had grown to 65 miles one way, averaging three hours a day.  I was growing tired of top 40 music and news radio.  After a particularly late night at work, I was listening to my local NPR station when the broadcast for the local minor league baseball team came on.  While I had never been a sports nut, I found that the broadcaster (Mike Saeger, now of the San Antonio Missions) interwove the narrative of the game with fascinating stories about the team, the players and baseball’s past.  Unfortunately, it typically started at 7:00 or 7:30 in the evening, meaning that I would typically catch the first 30 minutes at best before arriving home.

My goal became to record the games to listen to on my commute.  At first I considered piping a radio into a sound card, but I couldn’t get the station in the mountains where I lived.  I eventually figured out that the NPR station broadcasting the games had a website with a live feed.  Upon further digging, I found that the station was using a RealPlayer streaming audio format for its live feed.

I looked at options for automated recording of the feed and was unimpressed with my options on the Windows platform.  After some searching, I found that mplayer on Linux could play a RealPlayer feed, and more importantly, it could record it to a PCM-coded WAV file.  Thus began my quest to build a recording rig.  My goal was to record the game to a WAV file and convert it into a low quality MP3 that I could play from my chewing-gum-pack sized Creative MuVo.

I chose Fedora Core as my distro, mainly because most of the relevant forum posts and blogs I found on the topic had a Fedora or Red Hat focus.  I downloaded Fedora Core 3 to a CD and looked through the scrap pile at work to find a suitable machine.  I wanted something with low power consumption, since California’s electricity rates were astronomical and this machine would be running 24/7.  I settled on a Dell Latitude C600 laptop.  It had a 750MHz mobile Pentium III and 192MB of RAM.  It had been relegated to the scrap heap because it had a weak battery, some missing keys and a broken screen, none of which would be an issue for my purposes.  More importantly, with the lid closed, it drew only 15 watts at full tilt and 12 watts at idle with the 60GB drive spun down.  The weak battery still lasted 30 minutes, which was enough to ride out most power interruptions.

I’m a command line guy–I had to be dragged kicking and screaming into Windows–so I deselected the GUI and went with a minimal install.  All told, the running OS took less than a gigabyte of disk space and 48 megs of the 192 megs of available RAM, leaving plenty for my tools.  I installed mplayer, sox and lame to handle the audio processing.  My shell script would spawn mplayer in the background, wait four hours, and then signal it to terminate.  Sox would then be launched to re-encode the stream into low bit-rate mono, which was then piped into lame to create the final MP3.  The encoding process would take several hours but still complete in time for me to download the file to my MP3 player the next morning.  Scheduling was done by looking at the team’s schedule at the beginning of the week and using a series of ‘at’ commands to run the script at the appropriate days and times.

As baseball season drew to a close, I looked for alternatives.  I looked at downloading NPR weekend shows like Car Talk and Wait Wait–shows that were not yet available as podcasts.  Those shows were available at NPR’s website, again in RealPlayer format.  However, the filenames changed each week, and the shows were broken into segments that had to be downloaded individually.  I was able to use wget to get the HTML for the page and grep to parse out the filenames into a text file.  I then fed the text file into mplayer, one line at a time, to download the segments.  Finally, I used sox to encode and concatenate the individual files into a single file, which was converted to MP3 by lame.

After about a year, I recognized a mistake I had made.  I chose Fedora Core not knowing about their support policy.  Fedora Core 3 only received security patches for about 16 months from its release, or less than a year after I installed it.  There was an unofficial process for upgrading to FC4, but it broke a lot of stuff and took a lot of cleanup.  After that upgrade, I left the system at FC4 until it was decommissioned.

This was my first real-world experience with Linux, and it really helped me to feel comfortable with the operating system.  While I have used Debian, Ubuntu, SuSE and other Linuxes, this experience with Fedora drove me to choose CentOS (or Red Hat if OS support is required) as my go-to Linux server OS.

Like many, I’ve dreamed of having a miniature datacenter in my basement.  My inspiration came from a coworker who had converted his garage into a datacenter, complete with multiple window A/C units, tile floor, racks and cabinets full of equipment and his own public Class C back when individuals could request and receive their own Class C.

I lived in a house in the mountains that had a fairly high crawlspace underneath, and I dreamed of some day scooping it out level, pouring cement and putting in a short server cabinet and two-post. To that end, I had a lot of equipment that I had saved from the landfill over the previous couple of years: old second generation ProLiants, a tape changer, a QNAP that had been discarded after a very expensive data recovery operation and an AlphaServer 4100.

However, there were two important lessons that I learned that changed my plans:  first, that home ownership can be very expensive, and something simple like pouring a floor was beyond both my abilities and my budget, and second, that electricity in California is ruinously expensive for individuals.  While commercial customers generally get good prices regardless of their usage, it doesn’t take many spinning hard drives before the higher residential tiers kick in at 35+ cents per kWh.  I think my coworker got away with it because he was doing web hosting on the side out of his garage at a time when web hosting still actually paid something.

Once I realized the sheer cost of having the equipment turned on, to say nothing of the cost of air conditioning the basement at the time when my poorly insulated house was already costing over $300 a month to cool during the summer, I gave up on my dreams and donated most of the equipment to that coworker.  My homelab ended up being a single core Dell laptop “server” with a broken screen that ran Fedora and consumed 12 watts.

Fast forward to 2016, and I realized that I needed to make a change.  Working as the sole IT admin in a SMB means that I always had zero to near-zero budget and had to assemble solutions from whatever discarded hardware and free software I could cobble together.  While that does provide some valuable experience, modern companies are looking for experience with VMware or Hyper-V on SAN or virtual SAN storage, not open source NAS software cobbled together and running QEMU on an old desktop.

I looked at building that homelab I always wanted, but again, electricity cost had only gone up in the intervening 15 years, and I was now in a transitional state of four people living in a two bedroom apartment.  I wasn’t willing to sacrifice what little tranquility we had at home by having a couple of R710s screaming in the living room.  Thus, I decided to build my own “servers.”

I already had built my “primary” desktop specifically to move some workloads off of my laptop.  It was an i5-4570S desktop with 6GB of RAM and a discarded video card that I used for light gaming and running one or two small VMs in Virtualbox.  My goal was to build two or three compact desktops I could run trialware on to familiarize myself with vCenter, SCCM and other technologies I was interested in.  By keeping the machines compact, I could fit them under my desk, and by using consumer-grade hardware, I could keep the cost, noise and power usage down.

To save space, I chose the Antec VSK2000-U3 mini/micro-ATX case.  Looking back, this was a huge mistake.  These are about the size of a modern SFF Dell case, but it is a pain finding motherboards and heatsinks that fit.  However, they did the job as far as fitting into the available space under the desk.  These cases use a TFX form factor power supply–common in a lot of desktop and SFF form factor Dells, so used power supplies are cheap and plentiful on eBay.

When choosing motherboards, my goal was to find a mini or micro-ATX board that had four RAM slots so I could eventually upgrade them to 32GB using 8GB sticks–not as easy a task as one might think.  The first motherboard I found on Craigslist.  It was a Gigabyte Mini-ATX motherboard with an i5-3470S CPU.  Due to the location of the CPU on the motherboard, I couldn’t fit it in the case without the heatsink hitting the drive tray, so I ended up swapping the mobo with the board in my home machine, as my nice Gigabyte motherboard and i5-4570S fit the Antec case.

Thinking I was clever, I chose an eBay take-out from an Optiplex 9010 SFF as my second motherboard.  It had four RAM slots and was cheaper than any of the other options.  However, I soon found out that Dell engineered that sucker to fit their case and no others.  Their proprietary motherboard wouldn’t fit a standard heatsink.  I ended up getting the correct Dell heatsink/fan combination from eBay, which fit the case perfectly and used a heat pipe setup to eject the heat out of the back of the case.  I also had to get the Dell rear fan and front panel/power button assembly to get the system to power on without complaining.  Fortunately, the Dell rear fan fit the front of the Antec case where Antec had provided their own fan, so no hacking was needed.  Finally, the I/O shield in the Optiplex is riveted into the Dell case and can’t be purchased separately, so I’m running it without a shield.  This system runs with an i5-3570K, which I rescued out of another dead machine I rescued from the trash.

Optiplex 9010 SFF heatsink, bottom view.  The end of the fan shroud on the left stops just millimeters from the rear grille of the Antec case, like they were made for each other.

Once the homelab was up and running, I upgraded RAM when I could afford it.  The two homelab machines and my desktop started out with 8GB each and now have 24GB each.  To further save electricity, I have them powered down when not in use.  (My primary desktop stays on, as it runs Plex and other household services.)  Right now, each system has a hard drive and a 2.5″ SSD.  (They have an empty optical drive bay, so additional drives can fit with a little work.)  I picked up some four-port gigabit Intel 1000 NICs (HP NC364T) since the onboard Realtek NICs on the Gigabyte boards aren’t picked up by ESXi.

So the big question: will these work with ESXi 6.7?  In short, no.  They run 6.5 Update 2 just fine, but the 3570K crashes when booting 6.7, possibly because it doesn’t have VT-d support.  However, they work great running 6.0 and 6.5, which will get me through my VCP studies.  For the price, power consumption, heat and noise, they do the job just fine for now.

Part 1 of this saga can be found here.

Good monitoring doesn’t come ready to use out of the box.  It takes a lot of work: deciding what to monitor, deciding on thresholds and when and how to alert.  Alert Fatigue is a thing, and the last thing you want is to miss an important alert because you silenced your phone to actually get a full night’s sleep.  But monitoring and alerting, if configured in a sensible way, can save hours of downtime, user complaints and the IT practitioner’s sanity.

I had been searching for monitoring utopia for more than a decade.  I tried Zenoss, Nagios and Zabbix on the FOSS side, and briefly toyed with PRTG and others before being turned down by management due to cost.  In every case, it took a lot of work to set up.  Between agent installation and updates, SNMP credential management, SNMPWALKing to find the right OIDs to monitor, and figuring out what and when to alert, monitoring in a mixed environment takes a lot of TLC to get right.

In my mini datacenter build, I had the opportunity to build my monitoring system the way I wanted.  I could have made a business case for commercial software, but this build and move already had taken a significant chunk of money–remember that the entire warehousing and shipping/receiving operation had also been moved and expanded.  And besides, having tested several of the commercial products, I knew that the initial setup probably would have been faster, but the ongoing work–tweaking thresholds, adding and removing sensors, and configuring monitoring–was going to take a lot of work regardless of the system I chose.

With that in mind, I chose Zabbix.  I had used Nagios in the past, but I preferred a GUI-based configuration in this case.  In an environment where I was deploying a lot of similar VMs or containers, a config file-based product like Nagios would probably make more sense.  Having chosen Zabbix, the question was where to install it.  At the time, Zabbix didn’t have a cloud-based product, and installing it within the environment didn’t make sense, as various combinations of equipment and Internet failure could make it impossible to receive alerts.

After looking at AWS and Azure, I went with simple and cheap: DigitalOcean.  Their standard $5/month CentOS droplet had 512MB of RAM, one vCPU, 25GB of disk space, a static IP and a terabyte of transfer a month.  I opted for the extra $1/month for snapshotting/backups, which would make patching less risky.

The first step was to set up and lock down communications.  I went with a CentOS VM at each of the company’s two locations and installed the Zabbix proxy.  The Zabbix proxies were configured for active mode, meaning that they communicated outbound to the Zabbix server at DigitalOcean.  pfSense was configured to allow the outbound traffic, and DigitalOcean’s web firewall restricted the Zabbix server from receiving unsolicited traffic from any IPs other than the two office locations.  Along with the built-in CentOS firewall, it was guaranteed to keep the bad guys out.  I also secured the Zabbix web interface with Let’s Encrypt, because why wouldn’t I?

Next up was configuring monitoring.  Zabbix comes with a Windows monitoring template.  After installing the agent on all of the Windows hosts and VMs, I configured monitoring by template.  I found it best to duplicate the base template and use the duplicate for each specific function.  For instance, one copy of the Windows template was used to monitor the DNS/DHCP/AD servers.  In addition to the disk space, CPU usage and other normal monitoring, it would monitor whether the DHCP and DNS servers were running.  Another copy of the template would be tweaked for the VM hosts, with, for instance, more sane disk space checks.  Linux monitoring, including of the pfSense boxes, was configured similarly.  Ping checks of the external IPs was done from the Zabbix host itself.

Environmental monitoring was also important due to the small closet size and lack of generator support for the building.  SNMP came to the rescue here.  Fortunately, I had two Tripp Lite and one APC UPS in that little server closet.  Using templates I found online, I was able to monitor battery charge level and temperature, remaining battery time, power status, humidity and battery/self test failures.  The Tripp Lite units had an option for an external temperature/humidity sensor, and I was able to find the remote sensors on eBay for less than $30 each.  One I mounted in front of the equipment in the rack to measure intake air temperature, and the other I mounted dangling in the airflow of the A/C to measure its output temperature.  That way, I would be alerted if the A/C unit failed, as well as monitor its cycle time and see how cold the output air was compared to historical data.

The primary infrastructure to monitor was the Hyper-V cluster.  Fortunately, I found a Hyper-V and CSV template online that I was able to tweak to work.  Not only did it monitor the CSVs for free disk space and connectivity, it could alert if either of the hosts had zero VMs in active status–an indication that the host had rebooted or otherwise lost its VMs.  A Dell template monitored server systems and could report a disk or fan failure.

No monitoring system is complete without graphs and alerts, so I built a custom “screen”, which is Zabbix terminology for a status dashboard.  I created a 1080×1920 portrait screen with battery and temperature graphs, a regularly updated picture of the interior of the room provided by an old Axis camera, and a list of active alerts and warnings.  I mounted a 1080p monitor in portrait orientation in my office and used an old PC to display the screen.

Finally, I tackled the issue of Alert Fatigue.  At a previous employer that had a 24-hour phone staff, I would receive eight to ten phone calls in the middle of the night, and of those calls, maybe only one a month would actually need my attention that night.  I vowed to tweak all of the unnecessary alerts out of my new monitoring system.

I used a generic IT Google Apps email account on the Zabbix server to send the alerts to my email.  I then set my GMail to parse the alert and, if the alert status was “Disaster”, forward it as a text message to my phone to wake me up.  I then went through all of my alerts and determined whether they were critical enough to get a “disaster” rating.  A VM that had just rebooted wasn’t critical.  The Windows service that recorded surveillance on the NVR not running was critical.  The power going out wasn’t critical.  The remaining battery dropping below four hours, indicating that the power had been out for over an hour, was critical.  By setting up my monitoring this way, I would still be awakened for actual issues that needed immediate correction, but less critical issues could be handled during waking hours.  I also tiered my issues to indicate when a problem was progressing.  For instance, I would get an email alert if the room temperature reached 75 degrees, a second at 80 degrees, and a phone alert at 85 degrees.  That would give me plenty of time to drive in or remote in and power down equipment.

Many alerts I disabled completely.  The Windows default template alerts if CPU usage reaches something like 70%.  Do I care if my VMs reach 70% CPU?  If I don’t care at all, I can turn the alert off completely.  If I’m really concerned about some runaway process eating CPU for no reason, I can tweak that setting so that I’m not alerted until the CPU exceeds 95% for 15 minutes continuously.  At any rate, that’s not going to be flagged as a “disaster.”

The Zabbix droplet worked great.  There was no noticeable downtime in the two years I ran it.  I was able to run about 2,000 sensors on that droplet with overhead to spare even with one vCPU and 512MB of RAM.  (DigitalOcean has since increased that base droplet to 1GB of RAM.)  I probably would have replaced my GMail-to-text kludge with PagerDuty if I had known better, as it can follow up alerts with automated phone calls.  at any rate, I slept much better knowing my environment was well-monitored.

Next time:  Lessons learned, or “What would I do differently today?”