What is DNS? Why does it matter?
DNS stands for the Doman Name System. It is a giant, distributed database of all the domain names and where they map to.
Doman names are cut into pieces separated by a dot '.'. The TLDs are the Top-Level Domains. This includes "com", "net", "edu", and "win". Anyone can ask the TLDs where they can find "facebook.com", for instance. And Facebook might have subdomains, such as "mail.facebook.com" or whatnot.
If DNS is down, there are a number of reasons WHY this might happen, but the universal effect is the same: NOTHING WORKS. Even if you know the IP address of the domain name, you are going to have to do some major hack-fu to load the website.
How can DNS go down? 99% of the time, it's because you lost connection to the internet. You'll know that your internet connection is bad because nothing works, and you can't load any sites.
However, for the rare occurrences when DNS is down AND you still have an internet connection, it can be down for a number of reasons:
- The TLDs are not working. Even if they weren't working, though, there are cached lookups held at your ISP level so you won't notice when they go down, even for hours at a time.
- The company's DNS isn't working. So facebook.com points to facebook's servers, but facebook's servers aren't working right. Maybe facebook lost their connection to the internet, or maybe they deployed some bad code or configs. Even then, if it's a very popular website (like facebook) they have protections in place for this sort of thing, and even when they get it wrong, your ISP will have a cache of the last responses.
- Hackery is afoot. Someone has hijacked their DNS records, or their IP addresses, or some other nonsense like DDOS or somesuch.
If I had to guess, I would say facebook is being targeted or taken out by someone or something.
IF it is true that they mucked with our elections, THEN I would reasonably believe that government actors (military?) would be involved in corrective action to neutralize the threat and punish those responsible.
*** dns.google can't find facebook.com: Server failed
Server: dns.google Address: 8.8.8.8
FB seems to be down. Everything else I've tried works fine.
For necessary sites, you need to have links to the IP addresses bookmarked.
Instagram is down as well. Mostly seems to affect FB and entities owned by FB.
I don't have Instagram. That's mostly for sharing phone photos, and I don't carry around a tracking device.
Some sites require you send the doman name as part of the HTTP request. An easy way to handle a DNS outage is to program your hosts.txt file.
Yes. I forgot about the hosts files, as I haven't done anything with it in years.