NinerNet Communications™
System Status

Server and System Status

NC036: Possible resolution of issues with Cloudmark/Shaw

12 September 2021 16:13:55 +0000

At the end of August we heard from Cloudmark that, “Due to the IP [of server NC036] being located in the Netherlands, it was automatically put into a lower sending class. The sending class has been increased so deliverability will improve.” Since that time it appears that emails to shaw.ca and a few other domains using Cloudmark have been delivered without delay.

If this situation continues, it’s yet another example of what can be achieved if Internet companies work together, rather than ignoring each other.

NC036: Problems with shaw.ca again

13 July 2021 19:21:41 +0000

Shaw Communications Inc. and their mail filtering sub-contractor (Cloudfilter/Cloudmark) are again delaying, and now even bouncing, email sent to shaw.ca addresses. However, we have no way of communicating with Shaw mail server admins, so we cannot talk to them about how their filtering practices are non-standard and unpredictable.

Our mail server is still/again not in any of the 250 major blacklists that we monitor, so it is unclear why Shaw/Cloudfilter are causing this problem. If you are a Shaw customer, we strongly recommend that you contact Shaw and complain. We also recommend that you do not forward your email to any addresses on their domain.


Update, 2021-07-13 15:45 (PDT): Bounce messages will contain this line, or something very similar to it:

host shw-central.mx.a.cloudfilter.net[3.96.81.40] refused to talk to me: 421 shw-ibgw-4001a.ext.cloudfilter.net cmsmtp too many sessions from 178.62.195.26 AUP#CNCT

Normally bounce messages can be easily deciphered, but even we don’t know what this means or how it makes any sense.

NC036: Email to shaw.ca delayed

7 June 2021 04:15:13 +0000

As of Sunday 6 June 2021 (Pacific Time), emails to shaw.ca are being delayed. This problem may also be affecting other domains owned by Shaw Communications Inc., but at this point we’re only aware of the issue affecting email to shaw.ca

The problem appears to be that Shaw has changed their MX record to point to a new, external mail filtering company. (The change is new; the mail filtering company is not new.) All emails to shaw.ca are being temporarily deferred, rather than hard-bounced. It’s unclear why this is, as our mail server’s IP address is not in any major blacklists of the approximately 250 that we regularly monitor. There is also no notice on Shaw’s “Service Updates & Outages” page, and no notification was received by Shaw customers of a planned outage.

We will continue to monitor this situation and, if we can, take any action to work around Shaw’s action and the unavailability of their mail system at the moment. If you have any questions in the meantime, please contact NinerNet support. If you yourself are a Shaw customer, we strongly recommend you contact them and voice your displeasure at your email being delayed and/or blocked.


Update, 2021-06-07 15:00 (PDT): We submitted two support requests to the company to which Shaw outsources their email, but they have been no help, suggesting that we have to contact Shaw directly. However, since they’re blocking our email and they don’t seem to have any kind of a corporate website, that’s rather difficult.

After our last reply to a ticket at 14:23 we checked the mail server to confirm that the copies to Shaw were blocked, and we found that almost all of the queued emails to shaw.ca addresses had been cleared; a few moments later all had been cleared and delivered.

So it seems that this issue has been resolved. However, we have had no contact from Shaw, so without an explanation for why their email stopped working we can’t be sure this won’t happen again.

NinerNet home page

Systems at a Glance:


Loc.SystemStatusPing
Server NC023, London, United Kingdom (Relay server), INTERNAL.NC023InternalUp?
Server NC028, Vancouver, Canada (Monitoring server), INTERNAL.NC028InternalUp?
Server NC031, New York, United States of America (Web server), INTERNAL.NC031InternalUp?
Server NC033, Toronto, Canada (Primary nameserver), OPERATIONAL.NC033OperationalUp?
Server NC034, Lusaka, Zambia (Phone server), INTERNAL.NC034InternalUp?
Server NC035, Sydney, Australia (Secondary nameserver), OPERATIONAL.NC035OperationalUp?
Server NC036, Amsterdam, Netherlands (Mail server), OPERATIONAL.NC036OperationalUp?
Server NC040, Toronto, Canada (Web server), INTERNAL.NC040InternalUp?
Server NC041, New York, United States of America (Web server), OPERATIONAL.NC041OperationalUp?
Server NC042, Seattle, United States of America (Status website), OPERATIONAL.NC042OperationalUp?

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