Hi, In my UHD logs I see: [DEBUG] [MPMD] Path MTU for address 10.20.101.1: 1500 [DEBUG] [MPMD] Path MTU for address 10.20.102.1: 8016 But "ip addr" shows that the mtu is 9000 on both 10 gbe interfaces on the the host and the usrp. This is point-to-point connected. What else could be causing this? Many thanks, Kevin

Hi Kevin, we probe the path MTU, not read it from the NIC, so it's possible that something along the way is restricting the MTU to your device 101.1. Maybe the device itself has a different MTU setting. --M On Mon, Jul 7, 2025 at 1:31 PM Kevin Williams <kevin.williams@vastech.co.za> wrote: > Hi, > > > > In my UHD logs I see: > > > > [DEBUG] [MPMD] Path MTU for address 10.20.101.1: 1500 > > [DEBUG] [MPMD] Path MTU for address 10.20.102.1: 8016 > > > > But “ip addr” shows that the mtu is 9000 on both 10 gbe interfaces on the > the host and the usrp. > > > > This is point-to-point connected. > > > > What else could be causing this? > > > > Many thanks, Kevin > > > _______________________________________________ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-leave@lists.ettus.com >

Hi Martin, Just for completeness in the mailing list, I found that rfnoc_image_builder was compiling an HG image for the N300 even with XG requested. Hard-coding XG options for HG as a workaround has fixed this problem. Kind regards, Kevin From: Martin Braun <martin.braun@ettus.com> Sent: Thursday, 10 July 2025 09:42 Cc: usrp-users@lists.ettus.com Subject: [EXTERNAL][USRP-users] Re: usrp reporting different mtu's? Hi Kevin, we probe the path MTU, not read it from the NIC, so it's possible that something along the way is restricting the MTU to your device 101.1. Maybe the device itself has a different MTU setting. --M On Mon, Jul 7, 2025 at 1:31 PM Kevin Williams <kevin.williams@vastech.co.za <mailto:kevin.williams@vastech.co.za> > wrote: Hi, In my UHD logs I see: [DEBUG] [MPMD] Path MTU for address 10.20.101.1 <https://url.za.m.mimecastprotect.com/s/sMxRC48w33i9omkFOfVi4qiP0?domain=10.20.101.1> : 1500 [DEBUG] [MPMD] Path MTU for address 10.20.102.1 <https://url.za.m.mimecastprotect.com/s/9hIKC58x44ipvxNtOhZikXjxA?domain=10.20.102.1> : 8016 But “ip addr” shows that the mtu is 9000 on both 10 gbe interfaces on the the host and the usrp. This is point-to-point connected. What else could be causing this? Many thanks, Kevin _______________________________________________ USRP-users mailing list -- usrp-users@lists.ettus.com <mailto:usrp-users@lists.ettus.com> To unsubscribe send an email to usrp-users-leave@lists.ettus.com <mailto:usrp-users-leave@lists.ettus.com>