https://redmine.pfsense.org/https://redmine.pfsense.org/favicon.ico?16780521162021-01-24T14:11:41ZpfSense bugtrackerpfSense - Bug #11291: WireGuard MTU Can Flap between 1420 and 1500https://redmine.pfsense.org/issues/11291?journal_id=504972021-01-24T14:11:41ZChristian McDonaldcmcdonald@netgate.com
<ul></ul><p>I've nailed down clear reproduction steps...assuming that you have a WG tunnel and it's corresponding wg interface assigned.</p>
<ol>
<li> Go to the WG interface configuration and click save and apply.</li>
<li> Check Status > Interfaces and the WG interface will have an MTU of 1500</li>
<li> Go to the VPN > Wireguard > Tunnel configuration and click save</li>
<li> Check Status > Interfaces again and the WG interface will now have an MTU of 1420</li>
</ol>
<p>This is obviously problematic and was discovered by OSPF adjacency issues because the remote end had a fixed MTU of 1420, which is the WG default. I've disable MTU mismatch detection on both ends for the time being.</p> pfSense - Bug #11291: WireGuard MTU Can Flap between 1420 and 1500https://redmine.pfsense.org/issues/11291?journal_id=505012021-01-25T07:22:35ZJim Pingle
<ul><li><strong>Status</strong> changed from <i>New</i> to <i>In Progress</i></li><li><strong>Assignee</strong> set to <i>Jim Pingle</i></li></ul> pfSense - Bug #11291: WireGuard MTU Can Flap between 1420 and 1500https://redmine.pfsense.org/issues/11291?journal_id=505042021-01-25T07:40:08ZJim Pingle
<ul><li><strong>Status</strong> changed from <i>In Progress</i> to <i>Feedback</i></li><li><strong>% Done</strong> changed from <i>0</i> to <i>100</i></li></ul><p>Applied in changeset <a class="changeset" title="Use correct default MTU for WireGuard. Fixes #11291" href="https://redmine.pfsense.org/projects/pfsense/repository/2/revisions/8b9d2275015be7bf8febb1714f8a979d7c5f2beb">8b9d2275015be7bf8febb1714f8a979d7c5f2beb</a>.</p> pfSense - Bug #11291: WireGuard MTU Can Flap between 1420 and 1500https://redmine.pfsense.org/issues/11291?journal_id=505132021-01-25T07:54:49ZChristian McDonaldcmcdonald@netgate.com
<ul></ul><p>Looks good, thanks for the quick update</p> pfSense - Bug #11291: WireGuard MTU Can Flap between 1420 and 1500https://redmine.pfsense.org/issues/11291?journal_id=505592021-01-26T15:27:22ZJim Pingle
<ul><li><strong>Status</strong> changed from <i>Feedback</i> to <i>Resolved</i></li></ul><p>MTU is stable on current snapshots. It's 1420 even after save/apply on an assigned interface.</p>