How to enable SSH access to Synology DiskStation
Log into your system with an administrator account and open the 1Control Panel applet. From there, click on 2Terminal & SNMP, 3Enabled SSH service, and 4Apply.
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It doesn’t get any easier than that! Check out the Synology Wiki for more information. You can log to the root account using your admin password. :)
ssh root@1.2.3.4