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Sendmail Problems

My isp blocks both outbound and inbound connections on port 25. Poses
a slight problem for sending and reciving mail.

I have found a site which will relay for me, but I do not have any
idea how to set up the sendmail prog to do this.

Given that inbound and outbound connections to 25 are also blocked, I
need to set up my system to

1) relay to a remote host to send email
2) relay to that host on a different port (Port 3325)
3) authenticate to that host

Can anyone either point me to a good webpage or provide some config
lines to add into the files, I would greatly appreciate it.


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1 Solution
you can use the following in your sendmail.mc file

dnl sendmail through your isp's mail server


DAEMON_OPTIONS(`Port=3325,Addr=, Name=MTA')
DAEMON_OPTIONS(`Port=987, Name=MSA, M=E')

and on authentication if you are using sendmail as a client (from http://www.sendmail.org/~ca/email/sm-812.html#812AUTH)

AUTH related

If sendmail acts as client, it needs some information how to authenticate against another MTA. This information can be provided by the ruleset authinfo. The authinfo ruleset looks up {server_name} using the tag AuthInfo: in the access map. If no entry is found, {server_addr} is looked up in the same way and finally just the tag AuthInfo: to provide default values.
The RHS for an Auth: entry in the access map should consists of a list of tokens, each of which has the form: "TDstring" (including the quotes). T is a tag which describes the item, D is a delimiter, either ':' for simple text or '=' for a base64 encoded string. Valid values for the tag are: U user (authorization) id
I authentication id
P password
R realm
M list of mechanisms delimited by spaces

Example entries are:

AuthInfo:other.dom "U:user" "I:user" "P:secret" "R:other.dom" "M:DIGEST-MD5"
AuthInfo:more.dom "U:user" "P=c2VjcmV0"

User or authentication id must exist as well as the password. All other entries have default values. If one of user or authentication id is missing, the existing value is used for the missing item. Realm defaults to $j and the list of mechanisms to those specified by AuthMechanisms.

Since this map contains sensitive information, either the access map must be unreadable by everyone but root (or the trusted user) or FEATURE(`authinfo') must be used which provides a separate map. Notice: It is not checked whether the map is actually group/world-unreadable, this is left to the user.

Notice: the default configuration file causes the option DefaultAuthInfo to fail since the ruleset authinfo is in the .cf file. If you really want to use DefaultAuthInfo (it is deprecated) then you have to remove the ruleset.


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