In order for your GroupWise system to receive messages from another GroupWise system via a dynamic Internet link, you need to create a DNS resource record for at least one of your GroupWise system's MTAs. The resource record enables the MTA information, along with the Internet domain names associated with it, to be broadcast throughout the Internet.
You need to create the following resource records in DNS:
You can use your tool of choice to modify DNS. The following sections explain the information required and provide sample records.
You can create an "A" record to map your MTA's host (server or workstation) to its IP address. This allows you to use the "A" record name in the service ("SRV") or text ("TXT") record rather than the IP address, which has the advantage of allowing you to only change the IP address in the "A" record rather than each "SRV" or "TXT" record. The "A" record is required if you plan to use a "SRV" record.
The following text shows sample "A" records.
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; Address ("A") records
;
localhost IN A 123.0.0.1
novell IN A 123.456.78.90
groupwise IN A 123.456.78.91
support IN A 123.456.78.92
Host Name (column 1): Use the host name of the server or workstation that is running the MTA. In the above example, novell, groupwise, and support are all hosts that are running MTAs.
Class (column 2): Use IN to represent the Internet.
Type (column 3): Use A to specify an address record.
IP Address: Use the IP address of the server or workstation that is running the MTA.
You can use either a service record or a text record to map your Internet domain names to the MTA. The following text shows sample "SRV" and "TXT" records:
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; Service ("SRV") records
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gwmtp.tcp.novell.com 172800 IN SRV "1 0 7100 novell"
gwmtp.tcp.groupwise IN SRV "1 1 7100 groupwise"
gwmtp.tcp.groupwise IN SRV "1 2 7100 novell"
gwmtp.tcp.support 172800 IN SRV "1 0 7100 support"
gwmtp.tcp.support 172800 IN SRV "2 0 7100 novell"
;
; Text ("TXT") records
;
gwmtp.tcp.novell.com 172800 IN TXT "1 0 7100 novell"
gwmtp.tcp.groupwise IN TXT "1 1 7100 novell"
gwmtp.tcp.groupwise IN TXT "1 2 7100 groupwise"
gwmtp.tcp.support 172800 IN TXT "1 0 7100 support"
gwmtp.tcp.support 172800 IN TXT "2 0 7100 novell"
Service.Protocol.Name (column 1): The service must be specified as gwmtp. The protocol must be specified as tcp. The name corresponds to the Internet domain name you want associated with the MTA. In the above sample, novell.com, groupwise.novell.com, and support.novell.com are the Internet domain names defined in GroupWise.
Time to Live (column 2): TTL (time to live) is the amount of time the record is cached in memory so it doesn't have to be looked up again. TTL is specified in seconds. In the above sample, 172800 represents 2 days.
Class (column 3): Enter IN to represent the Internet.
Type (column 4): Enter SRV to specify a service record. Enter TXT to specify a text record.
Priority (column 5): If an Internet domain name is associated with two different MTAs, the host with the lowest priority number is always contacted first. If two records with the same Internet domain name have the same priority, the weight number is used. In the above example, the two groupwise.novell.com records have the same priority, so the weight would be used.
Weight (column 6): The weight number specifies how to allocate connections among hosts with equal priorities. In the groupwise.novell.com record above, the novell host and the groupwise host have equal priorities, but the novell host has a weight of 1 and the groupwise host has a weight of 2. This means that 1 out of 3 times the novell host would be contacted first, and 2 out of 3 times, the groupwise host would be contacted first.
Port (column 7): The port number specifies the TCP port on which the MTA listens for incoming messages. The default port number for the MTA is 7100.
Host (column 8): The host specifies the host name or IP address of the server or workstation where the MTA runs. For a service record, you must specify the host name. For a text record, you can specify either the host name or the IP address of the host. If a host name is used, its IP address must be specified in an address record. In the above example, novell, groupwise, and support are all hosts that have "A" records in DNS.