The routing table is where you define how you want to handle messages for each domain you host. It supplies Alligate with the information on how to validate recipients and where to deliver messages that are are not rejected.
Primary Domains: A primary domains would typically be considered a "root" or main domain. Other domains you want to accept mail for that will go to the same mail server with the same caching preferences as the primary domain can be added under Additional Domains. You can add as many primary domains (routing definitions) as you want. However, if you are using the BASIC or ADVANCED versions, only the first routing definition will be used. You must be licensed for the PRO version to utilize multiple destination servers.
Destination IP Address: This entry contains destination IP addresses that Alligate should deliver messages to for the domains entered. You will note that this area can contain several IP addresses. This is to allow you to specify additional mail servers for load balancing or backup server failover operation. If you specify multiple addresses, behavior will be governed by what you have set in the dropdown box at the bottom of the tab page with the caption: If multiple destination IP addresses are defined, use. You have 2 options here.
Failover mode: In the event that the first mail server defined in the Destination IP Address box is unreachable, it will start delivering to the second server. If the second server is unreachable, it will go to the third server, and so on. The failover thresholds are preset to fail a server when the following conditions occur. There are 50 consecutive failures attempting to contact a destination server, or there are 20 failures in a 60 second period of time. These threshold parameters can be changed in the registry if necessary.
Round robin load balancing mode: If you select this option, and have 2 or more IP addresses defined as destination IP addresses, messages will be forwarded to destination servers in a round robin style rotation. This allows you to have 2 or more identical mail servers to distribute the load. If one server goes down, it will be taken out of the rotation using the same criteria as Failover mode.
In the event that a destination server goes down using either Failover or Load Balancing mode, Alligate will attempt to contact it every 60 seconds to see if the problem has been corrected. If it has, then it will be restored to "reachable" status and mail delivery will return to normal.
Processing Directory: This overrides the global processing directory for an individual routing definition. If you are using the Alligate AntiSpam add-in or some other custom scanner, you can specify what additional processing should be done for individual domain groups.
Destination SMTP Port: This entry should contain the TCP port that the destination mail server listens on.
Validate Recipients: This option specifies whether Alligate should validate recipients on the destination mail server(s) for the domains listed. This setting overrides any global settings.
Cache Recipient Responses: Specifies whether the recipient responses should in fact be cached, if recipient validation is enabled. This setting overrides any global settings.
Recipient Cache Size: Specifies the size of the cache in question. This setting overrides any global settings.
Additional Domains: Additional domains are domains that Alligate should also accept mail for, and deliver to the same server as the primary domain.
Alias Domains: Alias domains are two or more domains that have the share the setup/accounts on the destination server. This should only be used in conjunction with the Alligate Filtering plug-in, and with destination servers that support domain aliases.
Additional Domains: The prefix AGHMD plus the domain name of the defined primary domain plus a .TXT file extension.
Alias Domains: The prefix AGAL plus the domain name of the defined primary domain plus a .TXT file extension.
For example, if the primary domain for a particular routing definition is alligate.com, the Additional Domains file will be AGHMDalligate.com.txt and the Alias Domains file will be AGALalligate.com.txt. Similar files will exist for each routing definition and if no additional domains or aliases are defined, they will be 0 length files.
These files can be updated on the fly. Alligate will reload them automatically if they are modified. You do not need to restart the service. If you frequently add or remove domains, you can do a domain list dump from your mail server, give the output file the appropriate name, and push updates to the ..\Alligate directory on the Alligate server and no further intervention is necessary.
Alternate Recipient Validation Server IP: This entry can contain an IP address that Alligate can use as an alternate recipient validation server, as opposed to the server installed on the local machine. This can be useful in a clustered environment. See also Advanced Recipient Validation.
Alternate Recipient Validation Server Port: This entry can contain a TCP port that Alligate can use as an alternate recipient validation server, as opposed to the server installed on the local machine. This can be useful in a clustered environment. See also Advanced Recipient Validation.
The routing table data is maintained in a file in the ..\Alligate root directory named routing.txt. Whenever the routing table is changed, a backup copy is created in the ..\Alligate root directory before the changes are saved. They are saved as Copy (1) of routing.txt and so on. The structure is defined here.