Created attachment 193661 [details] gif(4) man patch with sysctl net.link.gre.max_nesting man gre(4) doesn't mention sysctl net.link.gre.max_nesting, which is necessary to create GRE-over-GRE. The attached patch adds section which is copy-paste from man gif(4) about similar sysctl.
I created a differential for further review.
A commit references this bug: Author: gbe Date: Fri Aug 21 07:03:54 UTC 2020 New revision: 364450 URL: https://svnweb.freebsd.org/changeset/base/364450 Log: gre(4): Mention sysctl for nesting gre tunnels PR: 228465 Submitted by: Sergey Akhmatov <sergey at akhmatov dot ru> Reviewed by: bcr Approved by: bcr MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D26097 Changes: head/share/man/man4/gre.4
A commit references this bug: Author: gbe Date: Fri Aug 28 08:50:08 UTC 2020 New revision: 364904 URL: https://svnweb.freebsd.org/changeset/base/364904 Log: MFC r364450: gre(4): Mention sysctl for nesting gre tunnels PR: 228465 Submitted by: Sergey Akhmatov <sergey at akhmatov dot ru> Reviewed by: bcr Approved by: bcr Differential Revision: https://reviews.freebsd.org/D26097 Changes: _U stable/12/ stable/12/share/man/man4/gre.4