Slack appears to be having issues for some people, with reports coming in of users who can’t connect to the service, receive errors when trying to send messages, and can’t even access Slack’s website. The issue doesn’t appear to affect everyone, and Slack hasn’t gone as far as calling it an outage on its status page. The differences in experiences pointed to a possible routing issue or the even more likely culprit, DNS (it’s always DNS).
At 3:50PM ET, Slack confirmed what we suspected and what others had already figured out — it was DNS.
Some of my co-workers have had issues today, while it’s working fine for others (including, unfortunately, me). It’s unclear how widespread the issues are — DownDetector only shows a thousand or so reports.
The company says it’s working on a fix for the issue, but the incident report page says it’s been ongoing since around 12:30PM ET, or 9:30AM PT.
If you’re still having trouble connecting, then either you or your ISP may need to flush your cached DNS information. One way to get connected if your ISP’s information hasn’t been updated is to use alternate DNS servers, like Google’s ( 22.214.171.124 and 126.96.36.199) or Cloudflare.
We are aware of connectivity issues related to DNS that are impacting a small subset of users. This issue was caused by our own change and not related to any third-party DNS software and services. In order to resolve this faster, your ISP (Internet Service Provider) will need to flush their DNS record for slack.com. Please reach out to your networking team to provide them with this information.
We expect all customers’ connectivity issues to be resolved within the next 24 hours. We know how important it is for people to stay connected and we apologize for this disruption.
If all that fails, maybe it’s the universe telling you to take a walk or cook yourself something nice. When the chat app eventually comes back, it’ll probably do so in a bit of a wave — you can just tell your boss that it came back a little later for you and that you were really trying to message them about that draft, honest.
Our investigation of this connection issue is still ongoing at this time. We’ll be back with another update and apologize for this disruption. Thank you for your continued patience. https://t.co/tZUb1TWDEc
— Slack Status (@SlackStatus) September 30, 2021
Update September 30th, 4:18PM ET: Added DNS outage information and possible fixes.