Use
the ExtendedRetry statement to extend the retry processing that Communications
Server SMTP (CSSMTP) uses when it attempts to resend mail messages
that are not immediately deliverable. For basic information about
extended retry, see the information about common
terms in z/OS Communications Server: IP Configuration
Guide.
The RetryLimit statement defines
the retry interval during which CSSMTP will try sending the mail
messages again while the JES spool file is still available. When the
long retry interval expires (the interval is the product of multiplying
the COUNT and INTERVAL values), the mail messages are copied to
a z/OS® UNIX directory for extended retry processing
and the JES spool file is released. When the extended retry interval
expires, the mail messages become undeliverable.
After
both the long retry interval and the extended retry interval retries
have expired, the following actions occur when information about the
mail sender's address is available:
- CSSMTP uses the setting on the ReturnToMailFrom parameter in the
UNDELIVERABLE statement to determine its next action.
- CSSMTP attempts to send the undeliverable mail notifications to
the originator of the mail message through the configured target servers.
If CSSMTP cannot send the notification on the first try, the mail
message becomes a dead letter (see UNDELIVERABLE statement)
and no retries will be made.
Guideline: If the ExtendedRetry
statement is not defined in the configuration file, extended retry
processing is inactive.
Tip: You
can set the Interval parameter on the ExtendedRetry statement to 0
to bypass extended retry processing.
Syntax
>>-ExtendedRetry--| Put Braces and Parameters on Separate Lines |-><
Put Braces and Parameters on Separate Lines
|--+-{----------------------------+-----------------------------|
+-| ExtendedRetry Parameters |-+
'-}----------------------------'
ExtendedRetry Parameters
.-Age 5----. .-Interval 30------.
|--+----------+--+------------------+--------------------------->
'-Age days-' '-Interval minutes-'
.-MailDirectory /var/CSSMTP/extwrtname/mail/-.
>--+--------------------------------------------+---------------|
'-MailDirectory mailDirectory----------------'
Parameters
- Age days
- Indicates the number of days that CSSMTP attempts to resend mail
messages after the extended term retry interval expires. The default
value is 5 days. The value 0 means that an unlimited number of retry
attempts will be made. The maximum value is 2147483647.
- Interval minutes
- Indicates the length of time, in minutes, that CSSMTP waits between
subsequent attempts to resend mail messages. The default value is
30 minutes. The maximum value is 1440 minutes (one day).
If the
Interval value is 0, no extended retry will be performed and a mail
message becomes undeliverable if CSSMTP cannot deliver it to the target
servers on the first try.
- MailDirectory mailDirectory
- The fully qualified directory name in the z/OS UNIX file
system where CSSMTP stores the mail message when the Interval parameter
is set to a nonzero value. Valid values are 1 - 512 characters in
length and must begin with a slash (/) to define the fully qualified
directory. The default mail directory is /var/cssmtp/extWrtName/mail/,
where extWrtName is the name specified in
the ExtWrtName statement.
Results: - A slash is added to the end of the mail directory name if it is
not present.
- If the mail directory does not exist it is created.
Guidelines: - The user ID that CSSMTP starts under must have read/write access
to this directory. If you are running multiple CSSMTP servers with
extended retry enabled, each server should have its own directory
and should not have access to the directories of other servers.
- Ensure that there is adequate space in the filesystem for extending
retry processing. For example, if each mail message is an
average of 8000 bytes in size and you expect to have 1000
mail messages to be tried again, then about 16 million bytes of file
space is needed [2 (files per mail message) × 8K (z/FS
file allocation size) × 1000]. Factor in the 75% threshold
for message EZD1862I, then the file system should be about 22 million
bytes in size (plus a margin of error).
- The size of the MailDirectory is the sum of all of the size of
all the mail messages saved for extended retry at any one time.
Restrictions: - If extended retry processing is activated, you must stop and restart
CSSMTP in order to change the name of the mail directory.
- If CSSMTP is active, you cannot change the name of the mail directory
and you cannot delete or change the files.
- The content of the files created by CSSMTP and stored in the mail
directory cannot be modified.
Tip: You
can configure your mail directory to be on a different z/OS UNIX file
system than where you have configured your deadletter directory. By
doing this, you can manage the resource better. For more information,
see UNDELIVERABLE statement.