User Guide

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IRONPORT ASYNCOS 6.3 FOR WEB USER GUIDE
DNS Options
Table 5-5 describes the DNS options for the advancedproxyconfig CLI command.
Table 5-5 advancedproxyconfig CLI Command—DNS Options
Option Valid
Values
Default
Value
Must Restart
Web Proxy?
Description
Enter the time to cache
successful DNS results if
DNS does not provide
TTL (in seconds):
0 - 86400 300 No Time to cache successful DNS results if
DNS does not provide TTL.
Enter the time to cache
results of DNS errors
(negative DNS caching)
(in seconds):
0 - 86400 30 No Set to 0 to be HTTP compliant.
Enter the URL format for
the HTTP 307 redirection
on DNS lookup failure:
String
with
EUN
page
variables
%P//
www.%
H.com/
%u
No URL format for the HTTP 307
redirection on DNS lookup failure. See
Table 12-2, “Variables for Customized
End-User Notification Pages,” on
page 244 for the list of valid variables.
Would you like the proxy
to issue a HTTP 307
redirection on DNS
lookup failure?
Yes , No
(Boolean)
Yes Yes Disable/Enable automatic HTTP 307
redirection on DNS lookup failure.
Would you like proxy not
to automatically failover
to DNS results when
upstream proxy (peer) is
unresponsive?
Yes , No
(Boolean)
No Yes Disable/Enable automatic failover to
DNS results when upstream proxy
(peer) is unresponsive.
Find web server by:
0 = use DNS answers in
order,
1 = use client supplied
address then DNS,
2 = use ONLY client
supplied address:
0, 1, 2 1 Yes Specify how the appliance should find
the location of the requested web
server.