22.214.171.124. Linux Operators and Wild Cards
In addition to merely entering a speciﬁc IP address or partial IP address in the
Allow or Deny list, you may also use any standard Linux operator or wild
card. In most cases, the only operator used is "EXCEPT" and the only wild
card used is "ALL," but more experienced Linux users may note that other
operators and wild cards may also be used.
This operator creates an exception in either the "allow" list or "deny" list.
For example, if the Allow list includes a line which reads
"192. EXCEPT 126.96.36.199," then all IP address that begin with "192." will
be allowed; except 188.8.131.52 (providing that this address appears in the
The ALL wild card indicates that all IP Addresses should be allowed or denied.
When ALL is included in the Allow list, all IP addresses will be allowed to
connect; conversely, if ALL is included in the Deny list, all IP Addresses will
be denied (except for IP addresses listed in the Allow list.)
For example, if the Deny list includes a line which reads
"ALL EXCEPT 184.108.40.206," then all IP addresses except
220.127.116.11 will be denied (except for IP addresses that are listed in the
An expression of the form "n.n.n.n/m.m.m.m" is interpreted as a "net/mask"
pair. A host address is matched if "net" is equal to the bitwise AND of the
address and the "mask."
For example, the net/mask pattern "18.104.22.168/255.255.254.0" matches
every address in the range "22.214.171.124" through "126.96.36.199."