Added optional TLS min/max protocol version and command line switches to set
versions for the etcd server.
If max version is not explicitly set by the user, let Go select the max
version which is currently TLSv1.3. Previously max version was set to TLSv1.2.
Signed-off-by: Tero Saarni <tero.saarni@est.tech>
To avoid inconsistant behavior during cluster upgrade we are feature
gating persistance behind cluster version. This should ensure that
all cluster members are upgraded to v3.6 before changing behavior.
To allow backporting this fix to v3.5 we are also introducing flag
--experimental-enable-lease-checkpoint-persist that will allow for
smooth upgrade in v3.5 clusters with this feature enabled.
The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
