Installation manual

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3.3.2.1.5.2 LBL (Last Blackhole List)
LBL servers: - The Last Connecting IP is queried against the LBL server. You can specify a different DNS lookup for
the last connecting incoming IP. For the last connecting incoming IP, the LBL list is queried instead of RBL list.
Otherwise, the RBL list options such as RBL threshold are also applied to the LBL list.
IP addresses not verified against LBL: - If the Last Connecting IP matches with an IP on the list, then that IP is
queried against the RBL server(s) instead of the LBL server(s).
To manage the list, use Add..., Edit... or Remove buttons.
The list consists of three columns:
Address
Response
Score
Here, you can specify IP addresses which will not be verified against LBL. To manage the list, use Add..., Edit... or
Remove buttons.
3.3.2.1.5.3 DNSBL (DNS Block List)
DNSBL servers: - Specifies a list of DNS Blocklist (DNSBL) servers to query with domains and IP's extracted from the
message body.
DNSBL verification sensitivity: - If score is greater than the "high" value then only those DNSBL servers which can
bring score below "high" value are queried. If score is less than the "low" value then only those DNSBL servers which
can bring score above "low" value are queried. If score is between "low" and "high" then all DNSBL servers are
queried.
DNSBL request execution limit (in seconds): - Allows setting a maximum timeout for finishing all DNSBL queries.
Maximum number of verified domains against DNSBL: - Allows limiting how many domains and IP's are queried
against the DNS Blocklist server.
To manage the list, use Add..., Edit... or Remove buttons.
The list consists of three columns:
Address
Response
Score
3.3.2.1.6 DNS
Use cache memory - Enable internal caching of DNS requests.
Number of DNS requests stored in memory: - Limits the number of entries in internal DNS cache.
Save cache memory to disk - If enabled, DNS cache will store entries on disk on shutdown and read from disk on
initialization.
DNS server address: - DNS servers can now be explicitly specified to override the default.
Direct DNS access: - When set to yes and if DNS server is not specified, then the antispam engine will make
LiveFeed requests directly to the LiveFeed servers. This option is ignored if DNS server is specified as it has
precedence. This option should be set to Yes when direct queries are more efficient than the default DNS servers.
DNS request lifetime (in seconds): - This option allows setting a minimum TTL for entries in the antispam engine's
internal DNS cache. The option is specified in seconds. For those DNS responses whose TTL value is less than
specified minimum TTL, the antispam engine's internal cache will use specified TTL instead of the TTL value of the
DNS response.