Lxc-create failed, unknow template

I use lxc1 2.0.11-0ubuntu1~16.04.3 for some reason, performed lxc-create -t download …etc,stopped the container, targziped it, than tried

lxc-create -n fromtemplate -t /root/lxc-template.tar.gz lxc-create: utils.c: get_template_path: 1418 No such file or directory - bad template: /root/lxc20-template.tar.gz lxc-create: lxccontainer.c: do_lxcapi_create: 1646 Unknown template “/root/lxc20-template.tar.gz” Error creating container fromtemplate
How to create custom template for LXC ( not LXD)? options like --fstree does not exists in my LXC.

Templates in the LXC world are shell scripts, you can’t pass a tarball as a shell script.

In 3.0 and higher the lxc-local does something close to what you want (but requires more files and a special layout).