I'm using pax to generate archives of ZFS snapshots on a FreeBSD machine, and restores may be accomplished under OpenBSD. I run both operating systems, along with some Debian and OpenSUSE. It's not an enormous amount of data, running about 350 GB.
Unfortunately, the FreeBSD pax command lacks the pax format supported by OpenBSD. I'm backing up paths that exceed the limits of ustar, so I'm looking at alternatives. I realize I could just use the various versions of tar or cpio, but I prefer the pax command line from a scripting standpoint. I was looking at the sv4crc, or sv4cpio formats as an alternative that is supported by both OpenBSD and FreeBSD. Does anyone have anecdotes, or caveats to share about sv4crc and sv4cpio pax formats? The man pages on OpenBSD, and FreeBSD don't seem to indicate any issues. I'm also doing some testing for my use case to make sure that they work properly. I'm just curious to hear other experiences. TIA, --Bruce