Skip to main content

domain name system - Is it possible to change MX records without downtime/returning/dropping messages?

We're migrating e-mail hosting from SERVER-A (on HOSTING_CO-A) to SERVER-B (on HOSTING_CO-B).



SERVER-A will continue to be functional until the transition is complete and HOSTING_CO-A has their own DNS server since our records currently show something that looks like:





mx1.hosting_co-a.example



ns1.hosting_co-a.example




and HOSTING-CO-B presumably has their own DNS servers as well (it is Google/GSuite).



I've read [1] that DNS changes may take up to 72 hours.




What would be the worst case scenario for what happens to an e-mail sent during this period?




  1. Would they either go to SERVER-A or SERVER-B (that is, would e-mail providers using non-updated DNS records be able to get through to SERVER-A or would SERVER-A reject or forward it based on its updated MX-record)?


  2. Would they be 'dropped' (that is neither the sender nor recipient will be aware that the message didn't go through)?


  3. Would the sender be notified that the message was not delivered?




We are switching over various domains/accounts, for some domains we'd rather messages be dropped than returned, and for others, we'd rather returned than dropped - if this is even something that can be controlled.




[1] https://support.google.com/a/answer/45679?hl=en Also points out reducing TTL for records in advance (would this mean a maximum downtime of your TTL?)

Comments

Popular posts from this blog

linux - iDRAC6 Virtual Media native library cannot be loaded

When attempting to mount Virtual Media on a iDRAC6 IP KVM session I get the following error: I'm using Ubuntu 9.04 and: $ javaws -version Java(TM) Web Start 1.6.0_16 $ uname -a Linux aud22419-linux 2.6.28-15-generic #51-Ubuntu SMP Mon Aug 31 13:39:06 UTC 2009 x86_64 GNU/Linux $ firefox -version Mozilla Firefox 3.0.14, Copyright (c) 1998 - 2009 mozilla.org On Windows + IE it (unsurprisingly) works. I've just gotten off the phone with the Dell tech support and I was told it is known to work on Linux + Firefox, albeit Ubuntu is not supported (by Dell, that is). Has anyone out there managed to mount virtual media in the same scenario?

hp proliant - Smart Array P822 with HBA Mode?

We get an HP DL360 G8 with an Smart Array P822 controller. On that controller will come a HP StorageWorks D2700 . Does anybody know, that it is possible to run the Smart Array P822 in HBA mode? I found only information about the P410i, who can run HBA. If this is not supported, what you think about the LSI 9207-8e controller? Will this fit good in that setup? The Hardware we get is used but all original from HP. The StorageWorks has 25 x 900 GB SAS 10K disks. Because the disks are not new I would like to use only 22 for raid6, and the rest for spare (I need to see if the disk count is optimal or not for zfs). It would be nice if I'm not stick to SAS in future. As OS I would like to install debian stretch with zfs 0.71 as file system and software raid. I have see that hp has an page for debian to. I would like to use hba mode because it is recommend, that zfs know at most as possible about the disk, and I'm independent from the raid controller. For us zfs have many benefits, ...

linux - Awstats - outputting stats for merged Access_logs only producing stats for one server's log

I've been attempting this for two weeks and I've accessed countless number of sites on this issue and it seems there is something I'm not getting here and I'm at a lost. I manged to figure out how to merge logs from two servers together. (Taking care to only merge the matching domains together) The logs from the first server span from 15 Dec 2012 to 8 April 2014 The logs from the second server span from 2 Mar 2014 to 9 April 2014 I was able to successfully merge them using the logresolvemerge.pl script simply enermerating each log and > out_putting_it_to_file Looking at the two logs from each server the format seems exactly the same. The problem I'm having is producing the stats page for the logs. The command I've boiled it down to is /usr/share/awstats/tools/awstats_buildstaticpages.pl -configdir=/home/User/Documents/conf/ -config=example.com awstatsprog=/usr/share/awstats/wwwroot/cgi-bin/awstats.pl dir=/home/User/Documents/parced -month=all -year=all...