Creative Productions, Arrangements and Operations • Art, Technology and Amusements. Software Engineer and certified FileMaker Pro developer and full-stack web developer by day, https//www.kupietz.com
If the web server is slow, detect a SYN flood by netstat -ant | grep :443 | grep SYN_RECV to show the IP addresses leaving it hanging. Hint: If you're behind a reverse proxy, and that shows IP addresses that aren't the proxy's, then your IP is being hit directly. To find out how many IPs are hanging, do netstat -ant | grep :443 | grep SYN_RECV | wc -l. If you do it a few times and the number is increasing, you may be under attack. If it's over 100, that's suspicious, but manageable and the server can usually handle it, especially if you have SYN cookies activated. If it's over 1000, you're under attack.
I got the error "The number of lookups on your SPF record exceed the allowed limit of 10. This will result in emails failing SPF authentication" in my Cloudflare DNS dashboard.
My spx record for, say, kupietz.com was "v=spf1 include:_spf.myEmailHost.com include:kupietz.com ~all"
Turns out, the problem is, every include can get parsed to be multiple servers. the include:kupietz.com apparently causes a recursive loop, creating more than 10 lookups. I updated it to "v=spf1 ip4:[my server's external IP address] include:_spf.google.com ~all", removing the recursive lookup, and adding my server's IP so it can send me administrative notices.
Also today my ISP changed my IP address unexpectedly... all DNS updated.
For confused first-time visitors and other people still acclimating, here is a description of these little tabs to the left, as well as some other features of the site.
Open "Expert Mode" CLI Navigation - this give you the option to switch your browser's display to an old-fashioned terminal mode where you may browse this site, view pages and images by typing text commands. Just like how we used to browse the web back in 1978!
Open Visual Settings - This gives you controls to customize the visual display of this website to your liking: turn up or down the brightness, contrast, color temperature, hue, saturation, dark mode, and earthquake. Settings are saved per browser tab, so they will be remembered for your whole visit.
Open My Eyes - Have you ever been engrossed in your work, when you suddenly realize someone is staring at your screen, watching everything you do over your shoulder? If not, this simulates the experience.
Open Help - This help popup, silly! You just clicked it! Do you not remember?
New - Draggable elements! Several elements on this website, including these tabs, this popup message, and the "Hire Mike" badge in the lower right, can be dragged around with your mouse, to avoid them blocking content. Positions are remembered per tab, so as you navigate around the site, they will stay in the same place for your whole visit.
Enjoy!
CLI Website Navigation
Are you sure you want to switch to viewing this website in the "expert mode" command-line interface?
This will switch to a terminal emulator, load this page, and allow you to browse this website and view its contents by typing text commands.
Plus there might be, y'know, some fun stuff hidden in there. Just for geeks.
