Version used: SLE-12-SP2-Server-DVD-x86_64-GM-DVD1.iso

uname -a; # version used
Linux linux-mbha 4.4.21-69-default #1 SMP Tue Oct 25 10:58:20 UTC 2016 (9464f67) x86_64 x86_64 x86_64 GNU/Linux

# check if firewall accepts incoming TCP connections on port 22
iptables -nL | grep 22; # = empty => you have to add firewall rule

yast firewall; # fire up SUSE firewall config gui, which is pretty self-explanatory

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