Significant Dropped Packets on WG interface

[Mike O'Connor]

Hi All

So after dropping all the way down to 1364 I'm still getting a lot of
dropped packets, only at one end.

A ping test using 'ping -M do -s 1472 IP' works from both directions but
1473 does not.

I really think there is something else wrong, but I had no idea what.

Mike

On 14/5/20 6:45 pm, Roman Mamedov wrote:
> On Thu, 14 May 2020 16:35:30 +0930
> Mike O'Connor <mike at pineview.net> wrote:
>
>> Hi All
>>
>> For the last few weeks my Wireguard link which I use to as my default
>> gateway has been having issues with TCP connections stalling.
>>
>> I've been trying to work out what is wrong. I just noticed that the
>> Wireguard link has dropped packets at both ends.
>>
>> wg-p2p    Link encap:UNSPEC  HWaddr
>> 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
>>           inet addr:104.127.123.10  P-t-P:103.127.123.10 
>> Mask:255.255.255.248
>>           inet6 addr: 2506:c500:ff4:1::ab/64 Scope:Global
>>           inet6 addr: fe80::e6/64 Scope:Link
>>           UP POINTOPOINT RUNNING NOARP  MTU:1500  Metric:1
> Reduce MTU of the WG interfaces to accomodate for overhead. See 
> https://www.mail-archive.com/wireguard@lists.zx2c4.com/msg01856.html for
> calculations of by how much.
>
>>           inet6 addr: 2506:c500:ff4:1::aa/64 Scope:Global
> I wonder what's this IP range, is this some VPN service? Squatting on
> unassigned IPs within 2000::/3 seems like a very bad practice. If they wanted
> an imaginary GUA for their NAT66, I'd suggest something like 66::/16 instead.
>