Login to portal admin, by using portal admin account
https://gis1.victorvilleca.gov/portal/portaladmin
portal admin, click home , click machine
Check whether your portal working correctly
If portal DNS web adaptor machine is down, then you will see only internal portal running here, public facing portal (through DNS web adaptor will not working)
see my another post here
https://transparentgov.net/cleargov1/1488/why-my-enterprise-portal-suddenly-stop-working