SG300 Loosing access to Web-Interface

[fabian.hahn]

We have several dozen SG3x0 switches in our network.  All switches work flawless and are accessible via ssh.  Only the web-interface does not respond. Basic SSL-negotiation seems to work – we get the Firefox "Illegal Cert – proceed with caution" message but no login-screen.

We updated switches to SW 1.4.11.4, also we changed to FindIT Manager

2.0.1.20191008 recently.  

The obvious we checked: 

ip http secure-server
no ip http server

No other changes I am aware of.  Any ideas why this might happen?

[marce1000]

 - Some suggestions 1) Try with other browser 2) Check the logs upon failed access to GUI

   M.

[fabian.hahn]

Thanks for your tip.  It turns out, it was a combination of the URL-rewriting to IP-numbers that the SG300 web-interface does and a badly configured proxy-sever.