HostsFile
Specify alternative /etc/hosts file V8.7 and later
When canonifying a host’s name,
sendmail will use the method
described under the ServiceSwitchFile
option (ServiceSwitchFile on page 1088). When
that method is files
, sendmail
parses the /etc/hosts file to
find the canonical name. If a different file should
be used on your system, you can specify it with this
HostsFile
option:
O HostsFile=path ← configuration file (V8.7 and later) -OHostsFile=path ← command line (V8.7 and later) define(`confHOSTS_FILE',path) ← mc configuration (V8.7 and later)
Here, path
is of type
string. If
path
is missing, the
name of the /etc/hosts file
becomes an empty string. If the entire option is
missing, the default is the value that was given to
_PATH_HOSTS when sendmail was
compiled (_PATH... on
page 131). If the path
cannot be opened for reading (for any reason at
all), host canonification by this method is silently
skipped.
One example of a use for the HostsFile
option would be to use a
switched-service file to cause all host lookups to
use DNS first, and then files:
hosts: dns files
In that case, you would use a special file to hold information about internal hosts which are not known to DNS. Such a file might look like this:
123.45.67.89 secret.internal.host.domain
This special file would be defined with the HostsFile
option.
The HostsFile
option is not safe. If specified from the command
line, it can cause sendmail to
relinquish its special privileges.
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