Category: DNS

DKIM Signing Outbound Email

We began signing outbound mail flows for and several weeks ago and have started to sign all customer owned domains this morning. This should be seamless for most customers, however, in some cases you may receive special instructions from us in order to enable it for your domains. Having aligned DKIM and SPF has become increasingly important to ensure reliable email delivery, especially into large providers like Gmail, Yahoo and Microsoft. We have chosen not to add DMARC records to customer domains at this time.

Please note, that if you use a third-party service provider such as Mailchimp, Constant Contact, Salesforce or Shopify to send email from either your or hosted domain you will most likely need to take action to ensure this email will continue to be delivered as expected. Importantly, you will not be able to send mail through a third-party service from a “” address. (These messages can, of course, have a reply-to to your “” address.) If you do use a third-party service, you will need to work with their customer service to ensure your mail flows will not be affected.

Please direct any questions or comments to

SPF record added to domains with Sonic DNS & Email hosting

Today on August 22, 2022, we added a default SPF (Sender Policy Framework) record to every customer domain name that has Sonic DNS hosting and email hosted with Sonic.

On August 15th, we emailed everyone who would be impacted by this change. The email subject was “Important information about your Sonic domain email hosting” and included a list of domain names that would be updated.

If you did not receive the email or do not have domain email and DNS hosting with Sonic, this notification does not apply to you.

If you received the above notification email and did not opt out or add an SPF record before today, the following SPF record was added to your domain:

"v=spf1 ~all"

For more information, please see our help document SPF and Sonic. To learn more about SPF, see Sender Policy Framework on Wikipedia.

We made this change to fight spam & phishing and to help ensure reliable email delivery for our domain email customers. SPF tells other email providers that Sonic is authorized to send email on behalf of these hosted domain names.

Northern California Network Core Maintenance

Update(1:10AM): Maintenance successfully completed.

Tomorrow (9/17/20) at 11:59PM we will be performing maintenance on core network hardware in our Santa Rosa data-center.  We expect this maintenance to be non-intrusive, but has the potential to impact a wide range of enterprise and Sonic hosted services.  The maintenance window will be 4 hours.

– Network Engineering

Sonic Data Center Core Maintenance – Night 2 of 2

Update(1:50AM) Maintenance ran long due to unforeseen hardware issues, but all work has been been successfully completed.

Wednesday, January 8, starting at 11:59pm, we will be performing maintenance on core equipment in our Santa Rosa HQ Data Center. Minimal customer impact is expected, with brief periods of routing instability towards some Sonic services, such as web-hosting, email and Member Tools. This maintenance window is 4 hours.

-Network Engineering

Sonic Data Center Core Maintenance – Night 1 of 2

Update(1:20AM) All work for tonight has successfully concluded.

Tuesday, January 7, starting at 11:59pm, we will be performing maintenance on core equipment in our Santa Rosa HQ Data Center. Minimal customer impact is expected, with brief periods of routing instability towards some Sonic services, such as web-hosting, email and Member Tools. This maintenance window is 4 hours.

-Network Engineering

San Francisco Collocation Power Maintenance

This Saturday (6/9) starting at 5AM, one of the San Francisco data centers we collocate equipment, will be performing a planned power maintenance. Although we have been assured by the colocation provider this work will be non-impactful, we have taken additional preparations to verify redundancy on all critical hardware, and will have a network engineer on site as a fail-safe.  The maintenance window officially extends until 6PM, and we will provide update when all work is completed.

– Network Engineering

(Update 8:12am) – We had a Power supply fail in a piece of our equipment during the first phase of the datacenter power maintenance.  We quickly swapped out the cabling to restore the unit.  Legacy DSL customers would have been impacted but service should now be restored.


Update(1:03pm) Power maintenance complete.

intermittent dns failure

Between 5:00 pm yesterday and 9:00 am today, customers may have experienced intermittent DNS failures or slower than normal name resolution. At 9:00 am this morning we noticed a configuration failure on one of our name server clusters. We immediately disabled the cluster which allowed traffic to flow over to our other redundant cluster. We have since addressed the issue and restored the cluster to working service. We are currently investigating our monitoring procedures to identify why this issue wasn’t detected earlier and to make sure it doesn’t happen again. We apologize for any inconvenience this may have caused.

– William & Kelsey

Updates to Our Recursive DNS Servers

On the morning of  Tuesday the 22nd, we will block access to our recursive DNS servers from off of our network.  This will help reduce the use of our DNS servers as part of the ongoing DNS Amplification Attacks as well as protect their quality of service for all of our customers.  This will, however, cause issues for any roaming device that has our DNS servers hard coded.  These devices should be configured to use server assigned DNS settings instead.  For more information please see our forums.

-Kelsey and William


Slow DNS responses this morning

This morning approximately between 6:30 AM and 7:00 AM, users may have noticed slow or dropped responses to our recursive dns servers. Further investigation discovered this interruption was caused by a small reflective DOS attack. We are actively working on a solution to fix these DOS attacks that affect our dns servers and hope to have a solution soon. We apologize for not getting this notice out sooner when the problem occurred.

-William and the SOC

Unreachable Services

This morning, from around 2:10AM to 2:25AM, a large DDoS attack targeting an IP within our Santa Rosa datacenter caused reachability problems to some member and hosting services. The attack has been blocked and all reachability restored.

– Robbie