On February 25th, the Mac Roaming Client version 2.2.544 was pushed to a limited set of our Production customers to address DNS flapping issues for IPv6 on Big Sur.
A bug exists in this build which, in some cases, can result in temporary loss of DNS after a reboot has occurred.
A patched version has already been released that prevents this issue from occurring, but if you have already rebooted then manual resolution is required.
What to do
If you have 2.2.544 and have not yet rebooted
You have rebooted and not experienced any issues:
- A new version should be pushed to your computer automatically. To manually install this version, you can download and install the package from our release notes for 2.2.548 here.
- Click the Apple Icon at the top left corner of your screen
- Select System Preferences
- Select the Network Icon
- Click Advanced
- In the left hand pane, there will be a space for DNS servers. If there is a selectable entry for 127.0.0.1, select it and click the minus ("-") button to clear it from the list. (If the IP is greyed out/unelectable, go to Alternative Mitigation section at end of this document).
- Click Okay
- Umbrella should begin working again in approximately 1 minute as it detects the new settings
- To prevent this from reoccurring, make sure you are upgraded to 2.2.548.
Alternate Mitigation Solution:
1. Open a terminal
2. Run the following command:
for OUTPUT in $(networksetup listallnetworkservices | sed -n '1!p')
if [ $(sudo networksetup -getdnsservers $OUTPUT | grep -c 127.0.0.1) -gt 0 ]
networksetup -setdnsservers $OUTPUT "Empty"
If you have any further issues, please contact Umbrella Support.