- metadata: - source: https://overdr.ink/not-a-fifth-wheel/ --- # not a fifth wheel > ## Excerpt > Part 4 of 5 - follows on from; Part 3 - converged cluster The fifth server, certainly not a fifth wheel, was to be my existing Supermicro server, then eBay jumped out at me with another HPE Gen8 server. This was a piece of metal I have always thought was --- Part 4 of 5 - follows on from; Part 3 - [converged cluster](https://overdr.ink/converged-cluster/) The fifth server, certainly not a fifth wheel, was to be my existing Supermicro server, then eBay jumped out at me with another HPE Gen8 server. This was a piece of metal I have always thought was kinda cool. The DL580.  This computer was made for what one could describe as the late big iron era. Applications were scaled up not out. Big databases needed to support online transaction processing tended to run on large single operating system instances with shedloads of CPU and memory. Modern applications mostly scale out, with many smaller instances splitting up the workload on smaller distributed (cheaper) server instances. This comes with trade-offs as the nodes need to agree on consensus when it comes to single sources of truth. That is; additional latency is introduced while the nodes mutually agree which node has the correct copy (usually the latest) of the data. Anywhay, the big iron refers to very large servers that run important large applications. They mainly need lots of memory and plenty of hot-swappable components to support the applications. Just as a two node cluster becomes highly degraded (vulnerable) is a single node fails, big iron servers need to be able to have multiple components of the same type being replaceable, whilst the server and its applications continue to execute. These servers, the operating systems and applications that run on them can be analogously described as pets. They require nuturing and vetenerary services etcetera. Facebook and Google run their applications on extremely cheap swarms of servers. They do not have multiple power supplies nor redundant network uplinks. If they fail, the application's workloads running on them are absorbed by the swarm. Fault diagnostics is not undertaken. Perhaps a new operating system might be reinstalled, and the system restarted, but failure at that point would have the whole unit replaced with a fresh one that would automatically configure itself upon powerup. These systems of servers, operating systems and the atomic units of the workloads that run on them are often analogously described as cattle. And not the sweet, daisy the cow type of cattle, but the type Ronald McDonald is fond of. The late big iron era still had a few legacy applications that were pets and they require servers such as the HPE DL580. So I replaced my ageing Supermicro server with an HPE Gen8 Server. - 1x 2-port 10Gb 2P 534FLR-SFP+ ethernet - 10x SFF disk front-mounted disk slots - 9x PCIe slot - 4x Xeon E7-4880v2 2.5ghz, 15-Core, TDP 130W CPU - 512GB RAM memory (96 slots - max 6TB) - 4x 1500W redundant power supplies - 2x 300GB SAS spinning disks installed To this I added a 4x gigabit ethernet PCIe card and a SAS/SATA HBA to connect an external 3.5” spinning disk enclosure. I found a used Promise Vtrak JX30 3U JBOD chassis to fullfill this role as the Supermicro had my 3.5” disks mounted internally, yet the DL580 is not intended for bulk internal data storage. Data I care about is stored at rest on 8x 8TB 3.5” spinning rust disks, using the incredible ZFS filesystem. I run with two parity disks (meaning any two of the eight can fail before I lose data), resulting in a 48TB usable storage pool. This zpool is not a multi node storage system, and is only available to one physical server, and obviously, I attached the JBOD to the DL580. \[TBD: ZFS\] \[TBD: GPU workloads\] This machine is named node0. It is a pet ___ Part 1 - [What is Mini](https://overdr.ink/what-is-mini/) Part 2 - [home computing journey](https://overdr.ink/home-computing-journey) Part 3 - [converged cluster](https://overdr.ink/converged-cluster/) Part 4 - [not a fifth wheel](https://overdr.ink/not-a-fifth-wheel/) (this post) Part 5 - [our Mini computer](https://overdr.ink/our-mini-computer/)