“interface“ key word is used for Unnumbered IPv6 BGP session . You don’t have use mask (/24) while configuring neighbor , looks like FRR taking “1.1.1.1/24<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2F1.1.1.1%2F24&data=02%7C01%7Cvijayg%40vmware.com%7C322d165464954bb9239f08d71cc2a279%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637009494608378718&sdata=K1MHDYGfk8Dkj%2Be6fYZhDaaPxZcPZmLtm23lk58xtRo%3D&reserved=0>” as interface name. Thanks Vijay From: frog <frog-bounces@lists.frrouting.org> On Behalf Of Simon Jones Sent: 09 August 2019 08:40 To: frog@lists.frrouting.org Subject: [FROG] What's this 'interface' mean in 'neighbor' configure node ? Hi all, I found this is new in FRR compared to QUAGGA, what's this used for ? Why I should config interface first ? Is there some DOC about this ? # neighbor 1.1.1.1/24<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2F1.1.1.1%2F24&data=02%7C01%7Cvijayg%40vmware.com%7C322d165464954bb9239f08d71cc2a279%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637009494608378718&sdata=K1MHDYGfk8Dkj%2Be6fYZhDaaPxZcPZmLtm23lk58xtRo%3D&reserved=0> ... interface Enable BGP on interface # neighbor 1.1.1.1/24<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2F1.1.1.1%2F24&data=02%7C01%7Cvijayg%40vmware.com%7C322d165464954bb9239f08d71cc2a279%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637009494608388714&sdata=KfL%2F4CbKfWjQ9tqU4jHNJeiEa0spE%2BczOfDdbzw9Rk8%3D&reserved=0> remote-as 5001 % Create the peer-group or interface first or specify "interface" keyword % if using an unnumbered interface neighbor ---- Simon Jones