Canon VB101, Руководство пользователя

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54
Listing Guidelines
Descriptions in the Authorized/Restricted Host List are extremely complex, and errors in the
settings can result in access being prohibited where it should be permitted. To avoid this, follow
the guidelines given below with great care.
1.Left-align the mask
172.20.0.0/255.255.0.0 -- Correct
172.0.28.0/255.0.255.0 -- Incorrect
2.Use denied entries mainly rather than permitted entries.
!172.20.26.0/255.255.255.0
!172.20.28.0/255.255.255.0
3.Make permitted entries subsets of denied entries.
172.20.26.0/255.255.255.0
172.20.28.0/255.255.255.0
!172.20.0.0/255.255.0.0
4.List specific entries before generic entries.
Not like this:
!172.20.0.0/255.255.0.0
172.20.28.0/255.255.255.0
Like this:
172.20.28.0/255.255.255.0
!172.20.0.0/255.255.0.0
5.Avoid risky settings.
0.0.0.0/255.255.255.255
10.0.0.0/0.0.0.0
Such specification are not prohibited, but will effectively prohibit access from all hosts. Avoid
entry !0.0.0.0/0.0.0.0 in particular wherever possible.
Detail Settings
c
Note
●
The default value for "mask" is 255.255.255.255.
●
If you do not make a list, access is permitted to all hosts.
●
If the list provided prohibits access for all hosts, the Host Restriction
function is disabled and access is permitted to all hosts.
●
To prohibit access over HTTP connection via a proxy server, the address of
the proxy server must be set.
●
If you set the host restriction incorrectly, access to the settings page itself
may be denied. In this event, the problem can only be recovered by
restoring the factory default settings. (
→
P.160)