Webmin allowed IP addresses
As an extra security layer, we recommend that you limit access to Webmin to local IP addresses.
Enter IP addresses as a comma-separated list. IP subnets can be entered by typing address/mask. The mask can be either a network mask or a plain number, specifying the number of 1's at the left side of the network mask. Thus, a mask of 24 is equivalent to 255.255.255.0.
You can use this Wolfram Alpha widget to calculate which net mask corresponds to which address range.
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