Yes, allowing a single IP works. I've done this many times to allow targetted administration from a single remote location.
Possibly what we are dealing with then is a misconfigured network definition object. If you want to define the remote system by IP Address, then the definition needs to use the Host type. If you want it to be a self resolving FQDN, then it needs to be set as the DNS Host type. Extremely Important: No matter what type you set, leave the Interface setting at the default > setting.
Yes, allowing a single IP works. I've done this many times to allow targetted administration from a single remote location.
Possibly what we are dealing with then is a misconfigured network definition object. If you want to define the remote system by IP Address, then the definition needs to use the Host type. If you want it to be a self resolving FQDN, then it needs to be set as the DNS Host type. Extremely Important: No matter what type you set, leave the Interface setting at the default > setting.
Some other info for you guys -- sometimes an ISP will block port 4444 --- they will deny they are, until you provide evidence to the contrary. I had a skirmish with our primary ISP the other day, when I found that I could no longer connect to 2 different customers, on 2 different ISPs, that had their ASG's Webadmin set to port 4444 (for customers we install / setup / manage, we change that default to something else during setup). I argued and argued ... and finally they found that a new router they had installed on their end had a "mystery" ACL list in it... and TCP port 4444 was on the list.
They could not explain how / why it was there... I strained my tired memory to remember why we change those managed customer's ASGs to another port (I don't really believe in security via obsufucation), and then I remembered a Worm, at some point in the last decade, used that port, and ISPs when hog-wild blocking the port. A little research revealed it was the old "BLaster" worm that used port 4444. I guess what happened is the engineer that put this last router in had an ancient tome of an install document that recommended adding that ACL. Anyhow, the ISP removed the ACL, and all is well again.