ADC GUI is inaccessible.

Ping and CLI  is working.
/Var folder was normal.
Internal services are UP.
GUI is enabled for NSIP(if not use command : set ns ip <ip> <subnet> -gui enabled)
 

For NetScaler MPX/VPX:
You can restore GUI access via manually restart httpd process.

1: Kill all httpd related process
killall httpd

2: Confirm no httpd process running via below command NO output.
ps -aux | grep httpd | grep -v grep

3: Manually Start httpd process
/bin/httpd -f /etc/httpd.conf

After the httpd restart, the process was running and the GUI was accessible.

For BLX:
You can restore GUI access via manually restart nshttpd process.

1: Kill all nshttpd related process
killall nshttpd

2: Confirm no httpd process running via below command NO output.
ps -aux | grep httpd | grep -v grep

3: Manually Start nshttpd process
/usr/sbin/nshttpd -k start -f /etc/blx/nshttpd.conf

After the nshttpd restart, the process was running and the GUI was accessible.

Problem Cause