The SSL Visibility Appliance's WebUI can become unmanageable and extremely slow due to "Webserver Error" or "Error" pop-ups like the ones shown below.



  

A potential cause of these errors is that the configured DNS servers are unreachable or unresponsive. This issue has been seen more often when the SSL Visibility Appliance's management network settings are obtained by DHCP, since the DNS servers that get configured automatically may not be reachable without proper firewall rules or routing in place.

If the management network settings are obtained by DHCP, this issue can be resolved by switching to statically assigned addresses. When using statically assigned management settings, there is no option to configure a DNS server from either the CLD or front panel LCD. See the SSL Visibility Appliance Getting Started Guide for further details.

If the management network settings are statically set, and a DNS server was configured through the WebUI, a factory reset must be performed because you cannot modify the DNS settings from the CLD or front panel LCD.

 

Workaround

Ensure that any configured DNS servers can be reached by the SSL Visibility Appliance.