I recently had a Server 2019 crashing issue that was showing a 0x139 error (Kernel Security Check Failure). The event logs were full of TLS cipher errors, so we spent hours focused on that. However, it turned out the real problem was corruption found by SFC. DISM ended up needing an ISO source to help fix it. The TLS issues were just noise! I'm curious, what's the most misleading or false lead you've chased after during a production incident?
5 Answers
Speaking of tech troubles, I once spent nearly a year trying to fix these laptops that wouldn’t sleep or were waking up randomly! After exhausting all the software and hardware checks, I discovered it was just those silly camera covers from marketing blocking the trackpad. Who would have thought?
You wouldn’t believe how often I’ve ruled out routing issues only to find out it was asymmetric routing causing all kinds of chaos. I chased a network problem thinking it was in the domain controller, but it turned out the firewall was dropping some TCP traffic. So frustrating!
Oh man, I can relate! We had a bizarre issue where several internal servers were completely unreachable for a bunch of users on Chromium-based browsers. Oddly, it worked for Firefox and Safari users. After investigating for days, we thought it was a QUIC protocol issue based on the bizarre errors we were getting. We even disabled QUIC—not realizing there was a newer HTTPS record type in play. It turned out to be a DNS issue after all! No one expected that since we ruled DNS out twice, but the internal users were trying to use a certificate meant for external connections. We injected empty HTTPS records into our DNS, and voilà, problem solved!
That HTTPS record angle is nasty! The whole split setup and cache timing had to be so frustrating.
Blocking QUIC sounds like a solid move if you run into a similar conflict again.
Is this a tale as old as time? I can't even count how many times I've been like, 'It can't be DNS!' only to realize, surprise surprise, it actually was! I remember an incident where a floor of phones went down because the DNS settings were coded wrong in DHCP. PCs were fine, but the phones just couldn’t resolve their call manager. Total brain-buster that day!
You summed it up perfectly! "It's not DNS" is basically a tech mantra!
Been there. So many times!
I had one time where I was troubleshooting because a server wouldn't start after an update. I was convinced it was a problem with the configuration or software, but after tearing everything apart, I just realized I hadn't copied the SSL certificate folder over. Sometimes the simplest fixes are right in front of you!
I feel like all of us have those moments! You're deep in problems, and it's just a simple oversight.
It's wild how those things can get so convoluted. Asymmetric routing just doesn't make sense sometimes!