Hmmm I too thought that way.
lxd-p2c_3.4 (compiled in bionic)
is unable to transfer from xenial/x86_64 to another xenial server with (lxc - 3.0.1).
Generating a temporary client certificate. This may take a minute...
Certificate fingerprint: 9f545454655757586846d1d6245dab91657bb712c995
ok (y/n)? y
Admin password for https://1.24.4.4:8443
Error: Failed to rsync: exit status 2
[Receiver] Invalid dir index: -1 (-101 - -101)
rsync error: protocol incompatibility (code 2) at flist.c(2630) [Receiver=3.1.1]
but
lxd-p2c 3.0.0 can do it. (compiled on May 2,2018)
Another issue: Trying to transfer xenial/i386 system to another xenial server ((lxc - 3.0.1) gives this error (of course I try as root):
./lxd-p2c_3.0.0 https://1.2.3.4:8443 vm3 /
./lxd-p2c_3.0.0: 1: ./lxd-p2c_3.0.0: Syntax error: "(" unexpected
with lxd-p2c 3.4
-bash: ./lxd-p2c: Text file busy
lxd-p2c: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=3cff6b2cd5e3a7bd84e0389946cb47eff82356bc, not stripped
lxd-p2c_3.0.0: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=0f73a863186e0dd34d23a4bef2b1181dc1c366c5, not stripped
Any suggestions. Thanks