While working on the SSH issue some hosts where stuck in a reboot process that resulted in an outage for about 60 minutes. The affected hosts where:
Looks like SSH logins are failing. We're investigating.
Fixed.
We rolled out an invalid SSHd config which means that every user is locked out of SSH. Since that includes us, we now have to fix the config manually while the hosts are powered off. This will unfortunately take a while.
As the dashboard (dashboard.uberspace.de) accesses some user information via SSH, this also means that the dashboard is not working at the moment.
There is a major outage at our FRA3 site. We're investigating.
Recovery is done, systems are up and running.
The power to the rack has been restored, we are now in process of bringing the systems up again.
One of our racks at FRA3 has lost power (electricity). We are in contact with the on-site technicians of the data centre provider to figure out how to restore power.
Mails to Microsoft accounts are rejected, we are not given a reason and our request to unblock our mailgates is not responded to. We change the mail gateways as far as we can, but unfortunately the block seems to take effect after a few hours on the gateway we changed.
Google Mail (googlemail.com; gmail.com) no longer accepts mails when the sender domain does not have valid SPF and/or DKIM set up. To set up SPF and/or DKIM for your domain hosted at Uberspace.de, please refer to our manual.
Currently, we can not deliver mail to any t-online servers.
We can connect to t-online's MX servers again.
While we have no detailed information at this time, we suspect an error with t-online's infrastructure, as reported elsewhere on the net over the last hour. We keep investigating.
E.g. https://www.ifun.de/telekom-kunden-berichten-von-flaechendeckenden-e-mail-stoerungen-238410/
Since the end of last week we have been experiencing increasing problems with mail delivery to certain destinations from all uberspace.de hosts.
The exact cause is still is not yet known, but we are investigating and working on workarounds.
Mail delivery was rerouted from the individual hosts to our mail gateway. Delivery problems should be resolved.
We're checking our logs on a daily basis and identify domains, which are affected. We work around these domains on the next business day. So if you get a bounce for a domain you haven't sent a mail within the last two weeks today please try again the next day. We'll have that domain on our list by then.
Since we still haven’t received any helpful response from the reputation service provider, we have now implemented a permanent workaround for all domains with mail servers behind IronPort that we are aware of.
After a brief recovery, a large proportion of our hosts are now blocked again. While we continue to wait for answers as to why, we have now placed an smtproute over working hosts for all blocked hosts.
Apparently, a major provider of e-mail security solutions had classified us as “poor” - contrary to its publicly available information and initial responses to our inquiries - and blocked us on its IronPort firewall.
Unfortunately, despite several attempts, we still have no information about which patterns might have been responsible, but at least the block seems to have been lifted. Nevertheless, we will continue to monitor this closely.