By various well-paid supposed IT experts (usually instructed to "show me how to do my job properly", and often under "I must co-operate with them" clauses) I have been told, in earnest:
- Having an odd number of cores in a virtual machine will slow it down compared to having an even number, but less, cores.
- That a version of Linux back in about 2004 "could run everything Windows can" (and not via virtualisation). It was a cheap, shite remote-desktop service targeting schools. They wanted to replace the entire school with thin-clients and have all of them log into a remote Linux server. I would normally be RIGHT BEHIND that idea, except: They claimed that Wine could run *everything*, including Ranger ... which was an RM-made network management product aimed at Windows that operated by interfacing into the Windows GINA logins etc. and enforced settings in Windows, deployed security policies for the underlying OS, and basically "secured" the machine from people tampering with Windows settings etc. Apparently that would "just work" running under Wine to control those SAME settings in their Linux remote desktop. (P.S. the remote OS had a full suite of Microsoft Office icons that opened OpenOffice applications, which I reported as attempted fraud and breach of copyright/trademark).
- That it was "impossible" to have a Chromebook working with a major-brand web filter designed for schools. So when that was declared, I pressed "Enable" on a configuration that I had set up in ten minutes.
- Enabling spanning-tree will bring down the entire network, and "it never works".
- An at-length lecture about how NTP operates... when they were constantly referring to NTP Pool Project... which I run servers for. All kinds of nonsense was claimed there, complete disregard for strata, no idea how Windows actually syncs time, etc. etc.
- That a legitimate way to mass-deploy iPads with apps was to use a tool to suck out whatever the Apple equivalent of an APK file is from an existing iPad with licenced apps, then put them into an Apple Configurator profile and deploy every app to hundreds of iPads. Even legal use aside, when one day the apps all turned off (except on the original iPad) and everyone in the building started getting thousands of login prompts for accounts they did not own (the accounts those apps had originally been purchased for, once) making the iPads unusable. They doubled-down by charging by the hour to "fix them all" which consisted of them manually logging into a dozen different accounts on every iPad whenever prompted until the warnings went away... for about a week before they all re-appeared. That one, I actually laid down a "I will rebuild them all again, but this guy absolutely cannot be allowed anywhere near them" because of previous tampering when we re-imaged them without any such apps, and he put them back on. Strangely, without the illegal apps on them, they all worked and never provided spurious login prompts for things like "administrator@" our domain.
- Same guy thought that a legitimate way to image PCs was to take whatever the nearest computer was, make an image with Clonezilla onto a USB hard disk, then image it across to another machine, take it off the domain, rejoin the domain. We ended up with thousands of illegal copies of software, stupendous domain problems (because of the SID, naming etc. issues), and the image - after a year of him having been doing this before anyone else was hired to run the IT - was a humungous mess of confidential files, user profiles, software, taskbar icons and junk everywhere, gathered from every machine imaged and built up every time another machine was "imaged" and imaged and imaged in the same way after use by users. No sysprep, nothing.
- A server support engineer at a large MSP that was recommending, purchasing and servicing all the IT for a small one-server shop. They were asked to upgrade their storage as they were running low on space. Storage was all on one server, on a RAID5 set (at their previous recommendation!). The method by which they upgraded the storage was thus: Turn up. Pull hard drive #1 out while the machine is running live on production during the working day. Throw in a blank drive. Wait 8 hours for it to resync. Charge for 8 hours of sitting there watching a percentage bar with a cup of tea. Go home. Come in the next day. Pull hard drive #2 out. Throw in a blank drive. Wait 8 hours on a chargeable rate. etc. etc. etc. On drive #3, the resync failed, the RAID collapsed and it was unrecoverable. He was asked to restore the data to how it had been. "Oh, backups are your responsibility, not mine. Bye!" and literally walked away. He hadn't even checked before starting. (At which point I was dragged into the situation to try to salvage things back to some sanity and the MSP was dismissed from their contracts).
- A "network specialist" at an MSP (one we had to wait weeks to get their engagement because everyone else in the MSP had to defer to them because they knew nothing about networking themselves, and he was "the guy" for networking for the entire MSP) who couldn't - after months - work out why a VPN device that they insisted on (which was installed between two routers that had had an IPSEC VPN between them for years, no external device required) couldn't pass UDP broadcast traffic. They were even pre-warned, many times. They had the existing IPSEC, routing and firewall configuration to refer to. They put a VPN device behind the original devices that had been doing IPSEC happily for years and passing that traffic, sold it to the company for ridiculous money, and then couldn't get the single most vital - and warned about - application running across the link that had always worked before. It took literal months of tinkering, rebooting, rewiring, and then they declared it "impossible". At which point, I finally convinced my boss of the MSP's uselessness, removed the VPN boxes, and clicked the "enable" button on my existing configs at both ends again and... viola... perfect traffic passing.
- An "IBM" (I use the word dubiously as he worked on IBM systems but I think was actually unaffiliated with IBM) cyber-forensics engineer who was supposed to assist in recovering data (and verifying the extent of a compromise) from a corrupted / infected blade storage system. It took several days and basically consisted of him plugging his personal laptop into the blade server and copy-pasting what he could from an virus-ridden Windows server to his laptop, retrying whenever that failed, leaving it running overnight, etc. to then later try to present those files to us unsanitised on a USB created from that same machine. It took him most of the first day to work out how to actually get it working because we had isolated the machine entirely and refused to let him plug anything into the rest of the network - so even connecting a network cable direct to a laptop and configuring a static IP in a known range was completely beyond him.
- A former BT engineer trying to override my putting fibre into an existing building on the basis that "fibre is conductive" (and, no, the fibre in question didn't even have foil shielding, etc.)
And I have been asked, by those same kinds of people:
- "What's spanning-tree?" - in the mid 2010's.
- "What's virtualisation?" - in the mid 2010's.
- "What's a VLAN?" - in the mid 2010's.