W3 / Memcache & Multi Site Domains

Hey there! Have a wp multisite on a private VPS hosted and finally got memcache / memcached installed and working on our main site, so I can select it to perform various tasks in w3 cache

the problem is, when i go to general w3 settings for other sites in the network I see the below:
The following memcached servers are not responding or not running:
Database Cache:
Object Cache:
Page Cache:
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