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The SPF Setup Wizard
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Most domains send outbound mail through a relatively small number of servers. Domains should describe that set of servers in an SPF record in their DNS. Internet email receivers can then reject forged messages which don't come from an envelope sender domain's approved servers. This wizard helps domain owners identify all the servers which could be expected to send mail from their domain.

Let's set up SPF records for
lubrisyn.com's IP address is 216.26.151.48 (ideas.currentmarketing.com).
Does that server send mail from lubrisyn.com?
[a]
yes no
lubrisyn.com has one MX server, mail.lubrisyn.com.
It receives mail for lubrisyn.com.
Does it also send mail from lubrisyn.com?
[mx]
yes no
Do you want to just approve any host
whose name ends in lubrisyn.com? (Expensive, unreliable and not recommended)
[ptr]
yes no

Do any other servers send mail from lubrisyn.com?

You can describe them by giving "arguments" to the a:, mx:, ip4:, and ptr: mechanisms. mx: takes domain names and approves all the MX servers of these domains. To keep the wizard short we left out ptr:, but it works analogously.

[a:]
[mx:]

IP networks can be entered using CIDR notation, eg. 192.0.2.0/24
[ip4:]
Could mail from lubrisyn.com originate through
servers belonging to some other domain?
If you send mail through your ISP's servers, and the ISP has published an SPF record, name the ISP here.
[include:]
Do the above lines describe all the hosts
that send mail from lubrisyn.com?
[~all]
yes no
lubrisyn.com. IN TXT

The SPF record:

v=spf1 ip4:216.26.151.54 a mx include:aspmx.googlemail.com ~all

can be explained as:

[v=spf1] v=spf1This identifies the TXT record as an SPF string.
[ip4:] ip4:216.26.151.54 216.26.151.54 is allowed to send mail from lubrisyn.com.
[a] a lubrisyn.com's IP address is 216.26.151.48 (ideas.currentmarketing.com).
That server is allowed to send mail from lubrisyn.com.
[mx] mx lubrisyn.com has one MX server, mail.
It is allowed to send mail from lubrisyn.com.
If you add more MX servers in the future, they'll automatically be allowed, too.
[include:] include:aspmx.googlemail.com Any server allowed to send mail from aspmx.googlemail.com is also allowed to send mail from lubrisyn.com.
[all] ~all SPF queries that do not match any other mechanism will return "softfail".
Messages that are not sent from an approved server should still be accepted but may be subjected to greater scrutiny.

You need to transfer these records to your DNS server by yourself. No changes can be made by the wizard, it can only provide you with the data that needs to be entered into your DNS server.

If you run BIND

Paste this into your zone file:
lubrisyn.com. IN TXT "v=spf1 ip4:216.26.151.54 a mx include:aspmx.googlemail.com ~all"

When a mail server sends a bounce message, it uses a null MAIL FROM: <>, and a HELO address that's supposed to be its own name. SPF will still operate, but in "degraded mode" by using the HELO domain name instead. Because this wizard can't tell which name your mail server uses in its HELO command, it lists all possible names, so there may be multiple lines shown below. If you know which hostname your mail server uses in its HELO command, you should pick out the appropriate entries and ignore the rest.

So this should also appear in DNS. You may or may not be in charge of the DNS for these entries; if you are, add them.

mail.lubrisyn.com. IN TXT "v=spf1 a -all"

If you run tinydns (djbdns)

'lubrisyn.com:v=spf1 ip4\072216.26.151.54 a mx include\072aspmx.googlemail.com ~all:3600
'mail.lubrisyn.com:v=spf1 a -all:3600

If you run Windows DNS

Please see these instructions.

More options

If your site requires more complex configuration than this, you should read more about mechanisms. You should also review the tradeoffs involved in choosing an "all" default: see page 15 of the white paper.

You can test some pretend scenarios at one of the DNS tools. MTAs that reject mail because SPF tests failed will link to the why page.

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