TS5400R web interface stops responding

[mkelseywsu]

In a previous posting I identified a TS5400R having troubles enumerating user objects from AD.  This same TS5400R, although idle (unused but on the network) failed to respond to web management after being on the network for a little more than a week. 

I tested Chrome, Firefox, Midori and Internet Explorer from two different computers, but none of them ever succeeded in anything other than initiating a SYN packet on tcp/443.  The kernel of the TS5400R maintained a successful ping despite failing to serve web management.  It appeared as through web management UI process might have died off.

I connected a KVM and logged in as the admin account.  However, I was surprised to learn that neither reboot nor halt were available.  I kindly supplies an answer "No."

Being on a public network, I suspect any number of bad things could have been attempted against the user interface; so I'd like to ask opinions on

1. how to secure management and shares from unauthorized clients (subnets) without a dependency on an external filtering device.
2. how to resurrect the web interface when it fails.
3. how to determine why the web UI stopped responding.

[chelms@socal.rr.com]

I have an older TS-X4.0TL/R5 Terrastore, updated my firmware to 1.66 and IE11 stopped responding.  The login page just endlessly cycles.  The Terrastore Admin Web server also fails on Chrome 48, but with a different signature; the login succeeds but the admin web page immediately times out with the message, "The current session has expired. Please sign in again."  Strangely, Firefox 43.0.1 succeeds in logging me in.  This tells me there is something in the security settings that is different. 
Also note that Edge will complain about a certificate authentication error, that the certificate is not issued by the owner of the website, which would be Buffalo and the Terrastore.  I guess that's a clue also.

Seems like Buffalo needs to fix some browser compatibility issues.

[Eastmarch]

How many AD accounts do you think it's importing? Your previous post mentioned it was a lot. Might still be chewing on that.