| Fred Stluka via plug on 6 Feb 2021 11:27:15 -0800 |
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| Re: [PLUG] DOMAIN REGISTRAR |
Warning! I used to run my own DNS. The biggest problem was that you have to be up 100% of the time, or your email starts to get permanently rejected and you get removed from mailing lists. All without you having any idea that it's happening. Details: Email is a store-and-forward mechanism that tolerates lots of glitches and temporary outages. When A sends email to B, the email goes first from the mail client to the mail server used by that client. That's typically synchronous, so if it fails, the user sees an error and can re-try later. After that, it's all asynchronous via store-and-forward. The 1st mail server has a temporarily stored copy of the email and tries to forward it to the destination mail server, or to an intermediate server that will do so. (There used to be lots of servers involved as the mail was passed along until it finally reached the destination server, but these days, it's usually just one hop.) So the 1st server attempts to connect to the next server, and typically succeeds, deletes it's local copy, and we're all done. But sometimes, one of the server is temporarily down, or has an error, or rejects the email temporarily, or whatever. In that case, the previous server keeps it's local copy and tries again later, typically once an hour or so for typically 4 hours. After that, it typically sends a "bounce" message back to the original sender, saying that it's having trouble and will keep trying for typically 5 days. After 5 days of failing, it typically sends another bounce message to the original sender, saying it's is giving up and the email will not be delivered. (I say "typically" because these values and behaviors are all configurable on each mail server.) That works great, despite glitches, short-term outages, etc. Almost all mail eventually gets through if it's addressed correctly (and not filtered as spam, which is a whole separate issue). BUT... It all fails if the DNS server is down. In that case, the 1st mail server tries to look up the MX (mail exchange) record of the recipient's domain, fails because the DNS server is down, and immediately gives up. No point in re-trying to connect to the target server if it can't even find out the IP address of that target server. So, it immediately sends the final bounce message to the sender. That's a problem for 2 reasons: - The sender may be a person, who may or may not notice the bounce message, may or may not realize the mail didn't get through, and may or may not try again later or via a different channel (phone, text, social media, etc.) - More importantly, mail list software is typically configured to ignore the 4-hour bounce messages, knowing that the mail will probably get through later. But to react to the final 5-day bounce by REMOVING the recipient from the mailing list PERMANENTLY. Same for any other automated emailers, like notifications from your banks, from social media, etc. So, if you have a less than 100%-reliable server or Internet connection, it's fine to run your own mail server, but I strongly recommend against running your own DNS server. I finally stopped doing so, years ago, because the Internet connection to my house was unreliable. Now that my servers are hosted at AWS I could resume, but why bother? DNS is a truly mission critical service. And I do still re-boot my servers occasionally, which would cause brief outages. Hope this helps... --Fred ------------------------------------------------------------------------ Fred Stluka -- http://bristle.com -- Glad to be of service! Open Source: Without walls and fences, we need no Windows or Gates. ------------------------------------------------------------------------ On 2/6/21 6:57 AM, Casey Bralla via plug wrote:
I used to run my own DNS servers (BIND9). It wasn't too terribly difficult to setup, but it was not trivial either. (At one point I got used in a DDOS attack, so the security settings are crucial). I even did it with a "non-static" IP address because Comcast almost never change the IP unless the MAC of their router changed (like it did once when their provided router died).On 2/5/21 9:10 PM, Ronald P Guilmet via plug wrote:Thanks RichSo if I had a static ip you could use bind9 or something , or am I way off?On Fri, Feb 5, 2021 at 8:59 PM Rich Freeman <r-plug@thefreemanclan.net <mailto:r-plug@thefreemanclan.net>> wrote:On Fri, Feb 5, 2021 at 8:30 PM Ronald P Guilmet via plug <plug@lists.phillylinux.org <mailto:plug@lists.phillylinux.org>> wrote: > > Hey all, > > I am currently using Amazon Route 53 for my domain registration. They charge me for traffic that comes through those domains. I was looking to transfer to Gandi. Can anyone tell me if they charge for traffic through a domain. AWS isn't breaking the bank, but I feel like they are bleeding me at every angle. > > I started out as an AWS advocate, and I moved everything else away from them save the domains. > So, domain registrars don't pass traffic, and they almost never charge for anything besides renewals/etc, or maybe stuff like whois hiding. You're probably thinking about DNS service, which route 53 provides. Like everything with AWS they charge for every transaction - it has nothing to do with "traffic" per se but just how many times your domains get resolved. I use namecheap for DNS - they're free, though they do have some limitations. There are tons of DNS providers out there. One way or another you end up paying for this stuff but namecheap is about as cheap as it gets (they only provide free DNS for domains you register through them). You can also host your own DNS if you want, assuming you have a static IP. You would point your domain registry DNS server to your IP and run the authoritative DNS server of your choice. If you don't have a static IP you can't run your own DNS, but you could use a dynamic DNS provider (such as the free one from namecheap).-- Rich___________________________________________________________________________ Philadelphia Linux Users Group --http://www.phillylinux.org Announcements -http://lists.phillylinux.org/mailman/listinfo/plug-announce General Discussion --http://lists.phillylinux.org/mailman/listinfo/plug___________________________________________________________________________ Philadelphia Linux Users Group -- http://www.phillylinux.org Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug
___________________________________________________________________________ Philadelphia Linux Users Group -- http://www.phillylinux.org Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug