O OptionName=argument          # for the configuration file
-OOptionName=argument          # for the command line
define(`m4Name',argument)     # for m4 configuration

BadRcptThrottle

m4 name: confBAD_RCPT_THROTTLE

Argument: number

The new option limits the rate at which recipients in the SMTP envelope are accepted after a threshold number of recipients has been rejected. 

ClientPortOptions

For details, see New ClientPortOptions Option.

ConnectionRateThrottle

m4 name: confCONNECTION_RATE_THROTTLE

Argument: number

The option ConnectionRateThrottle now limits the number of connections per second to each daemon, not the total number of connections.

ControlSocketName

m4 name: confCONTROL_SOCKET_NAME

Argument: filename. The recommended socket name is /var/spool/mqueue/.smcontrol. For security, this UNIX domain socket must be in a directory that is accessible only by root.

When this new option is set, the option creates a control socket for daemon management. This option enables an external program to control and query the status of the running sendmail daemon by way of a named socket. The socket is similar to the ctlinnd interface to the INN news server. If this option is not set, no control socket is available.

DaemonPortOptions

For details, see Changes to DaemonPortOptions Option.

DataFileBufferSize

m4 name: confDF_BUFFER_SIZE

Argument: number

The new option controls the maximum size (in bytes) of a memory-buffered data (df) file before a disk-based file is used. The default is 4096 bytes. You should not have to change the default for the Solaris operating environment.

DeadLetterDrop

m4 name: confDEAD_LETTER_DROP

Argument: filename

The new option, which you should not need to set, defines the location of the system-wide dead.letter file, which was formerly hard-coded to /usr/tmp/dead.letter.

DelayLA

m4 name: confDELAY_LA

Argument: number

If this new option is set to a value that is greater than zero, the option does the following:  

Delays connections by one second when the load averages exceed a specified value 

Delays the execution of most SMTP commands by one second 

Otherwise, if the option is not set, the default value, which is zero, does not change the behavior of sendmail.

DeliverByMin

m4 name: confDELIVER_BY_MIN

Argument: time

The new option enables a client to specify a minimum amount of time for an email message to be delivered, as specified in RFC 2852, Deliver By SMTP Service Extension. 

If the time is set to zero, no time is listed. 

If the time is set to less than zero, the extension is not offered. 

If the time is set to greater than zero, the extension is listed as the minimum time for the EHLO keyword, DELIVERBY.

DirectSubmissionModifiers

m4 name: confDIRECT_SUBMISSION_MODIFIERS

Argument: modifiers

The new option defines ${daemon_flags} for direct (command-line) submissions. If this option is not set, the value of ${daemon_flags} is either CC f, if the option -G is used, or c u.

DontBlameSendmail

You can use the following new arguments. 

The argument, NonRootSafeAddr, has been added. When sendmail does not have enough privileges to run a .forward program or deliver to a file as the owner of that file, addresses are marked unsafe. Furthermore, if RunAsUser is set, users cannot use programs or deliver to files in their .forward programs. Use NonRootSafeAddr to resolve these problems.

DoubleBounceAddress

m4 name: confDOUBLE_BOUNCE_ADDRESS

Argument: address. The default is postmaster.

If an error occurs when sendmail is sending an error message, sendmail sends the "double-bounced" error message to the address that is specified by the argument to this option.

FallBackMXhost

m4 name: confFALLBACK_MX

Argument: fully qualified domain name. 

This option now includes MX record lookups. To use the old behavior of no MX record lookups, you must put the name in square brackets. 

FastSplit

m4 name: confFAST_SPLIT

Argument: number. The default value is one.

This new option does the following: 

If the option is set to a value greater than zero, the initial MX lookups on addresses are suppressed when they are sorted, which might result in faster envelope splitting. 

If the mail is submitted from the command line, the value can limit the number of processes that are used to deliver the envelopes. 

If more envelopes are created, the envelopes are put in the queue and must be resolved with a queue run. 

LDAPDefaultSpec

m4 name: confLDAP_DEFAULT_SPEC

Argument: Class switch with appropriate definition (for example, -hhost, -pport, -dbind DN).

The new option allows a default map specification for LDAP maps. The assigned default settings are used for all LDAP maps unless other individual map specifications are made with the K command. Set this option before defining any LDAP maps.

MailboxDatabase

m4 name: confMAILBOX_DATABASE

Argument: pw, which uses getpwnam(), is the default value. No other values are supported.

The new option specifies the type of mailbox database that is used to check for local recipients.  

MaxHeadersLength

m4 name: confMAX_HEADERS_LENGTH

Argument: number

This option specifies a maximum length for the sum of all headers and can be used to prevent a denial-of-service attack. The default is 32768. A warning is issued if a value less than 16384 is used. You should not have to change the default value for the Solaris operating environment.  

MaxMimeHeaderLength

m4 name: confMAX_MIME_HEADER_LENGTH

Argument: number

This option sets the maximum length of certain MIME header field values to x number of characters. Also, for parameters within headers, you can specify a maximum length of y. The combined values look like x/y. If y is not specified, half of x is used. If no values are set, the default is 0, which means no checks are made. This option is intended to protect mail user agents from buffer-overflow attacks. The suggested values are in the range of 256/128 to 1024/256. A warning is issued if values less than 128/40 are used.

MaxQueueChildren

m4 name: confMAX_QUEUE_CHILDREN

Argument: number

This new option limits the number of concurrently active queue-runner processes to the number that is specified in the argument. The option helps to limit the system resources that are used when the queue is processed. When the total number of queue runners for multiple queue groups exceeds the defined argument, the remaining queue groups are run later. 

MaxRecipientsPerMessage

m4 name: confMAX_RCPTS_PER_MESSAGE

Argument: number

If this option is set, the option allows no more than the specified number of recipients in an SMTP envelope. The minimum argument is 100. You can still declare this option from both the command line and the configuration file. However, normal users can now set the option from the command line to enable the override of messages that are submitted through sendmail -bs. In this instance, sendmail does not relinquish its root privileges.

MaxRunnersPerQueue

m4 name: confMAX_RUNNERS_PER_QUEUE

Argument: number. The default is one. Consider your resources carefully and do not set this value too high.

This new option specifies the maximum number of queue runners per queue group. The queue runners work in parallel on a queue group's messages. This behavior is useful when the processing of a message might delay the processing of subsequent messages. 

NiceQueueRun

m4 name: confNICE_QUEUE_RUN

Argument: number

This new option sets the priority of queue runners. Refer to the nice(1) man page.

PidFile

m4 name: confPID_file

Argument: See Additional Arguments for the PidFile and ProcessTitlePrefix Options.

This new option defines the location of the pid file. The file name is macro expanded before being opened. The default is /var/run/sendmail.pid.

PrivacyOptions

For details, see Changes to the PrivacyOptions Option.

ProcessTitlePrefix

m4 name: confPROCESS_TITLE_PREFIX

Argument: See Additional Arguments for the PidFile and ProcessTitlePrefix Options.

The new option specifies a prefix string for the process title that is shown in /usr/ucb/ps auxww listings. The string is macro processed. You should not have to make any changes for the Solaris operating environment.

QueueFileMode

m4 name: confQUEUE_FILE_MODE

Argument: number

This new option provides the default permissions in octal for queue files. If this option is not set, sendmail uses 0600. However, if the option's real and effective user ID is different, sendmail uses 0644.

QueueLA

m4 name: confQUEUE_LA

Argument: number

The default value has changed from eight to eight times the number of processors online when the system starts. For single-processor machines, this change has no effect. Changing this value overrides the default and prevents the number of processors from being considered. Therefore, the effect of any value changes should be well understood. 

QueueSortOrder

m4 name: confQUEUE_SORT_ORDER

This option sets the algorithm that is used for sorting the queue. The default value is priority, which sorts the queue by message priority. Note the following changes.

The host argument now reverses the host name before sorting, which means domains are grouped to run through the queue together. This improvement provides better opportunities for use of the connection cache, if available.

The new filename argument sorts the queue by file name. This behavior avoids the opening and reading of each queue file when preparing to run the queue.

The new modification argument sorts the queue by time of modification, starting with the oldest entries of the qf file.

The new random argument sorts the queue randomly, which avoids contention, if several queue runners have manually been started.

For more information, refer to QueueSortOrder in the sendmail(1M) man page.

RefuseLA

m4 name: confREFUSE_LA

Argument: number

The default value has changed from 12 to 12 times the number of processors online when the system starts. For single-processor machines, this change has no effect. A change of this value overrides the default and prevents the number of processors from being considered. Therefore, the effect of any value changes should be well understood. 

ResolverOptions

Two changes have been made. 

When attempting to canonify a host name, some name servers that are down return a temporary failure message, SERVFAIL, for IPv6 T_AAAA lookups. You can use this new argument, WorkAroundBrokenAAAA, to avoid this behavior.

Also, the RES_USE_INET6 argument is controlled by a new flag, use_inet6. For more information, refer to the resolver(3RESOLV) man page.

RrtImpliesDsn

m4 name: confRRT_IMPLIES_DSN

Argument: true or false

If the new option is set, a “Return-Receipt-To:” header causes the request of a delivery status notification (DSN), which is sent to the envelope sender. The DSN is not sent to the address that is specified in the header. 

SendMimeErrors

m4 name: confMIME_FORMAT_ERRORS

Argument: true or false.

The default is now true.

SharedMemoryKey

m4 name: confSHARED_MEMORY_KEY

Argument: number.

This new option permits you to use shared memory, if shared memory is available, to store free space for queue file systems. This option minimizes the number of system calls to check for available space. 

SuperSafe

m4 name: confSAFE_QUEUE

Argument: true, false, or interactive. The default and recommended value is true. Avoid using false.

If this option is set to true, the queue file is always instantiated, even if you are attempting immediate delivery. You can use the interactive value together with DeliveryMode=i to skip some synchronization calls that are doubled in the code execution path for this mode.

Timeout

For details, see Changes to the Timeout Option.

TrustedUser

m4 name: confTRUSTED_USER

Argument: user name or user numeric ID.

The new option enables you to specify a user name (instead of root) to own important files. If this option is set, generated alias databases and the control socket—if configured—are automatically owned by this user. This option requires HASFCHOWN. For information about HASFCHOWN, see Flags Used and Not Used to Compile sendmail.

Only TrustedUser, root, and class t ($=t) users can rebuild the alias map.

UseMSP

m4 name: confUSE_MSP

Argument: true or false. The default is false.

This new option permits group-writable queue files, if the group is the same as that of a set-group-id sendmail binary. In submit.cf, this option must be set to true.

XscriptFileBufferSize

m4 name: confXF_BUFFER_SIZE

Argument: number.

The new option controls the maximum size (in bytes) of a memory-buffered transcript (xf) file before a disk-based file is used. The default is 4096 bytes. You should not have to change this default for the Solaris operating environment.

AutoRebuildAliases

Because a denial-of-service attack could occur if this option is set, this option is not in version 8.12 of sendmail. Refer to the Release Notes that are part of the sendmail distribution at ftp://ftp.sendmail.org. A user could kill the sendmail process while the aliases file is being rebuilt and leave the file in an inconsistent state.

Furthermore, because AutoRebuildAliases is not available, newaliases must be run manually now in order for changes to /etc/mail/aliases to become effective. Also, you must remember that because sendmail is no longer setuid root, only root can run newaliases.

MeToo

This option, which now defaults to True, has been deprecated. Refer to the Release Notes that are part of the sendmail distribution at ftp://ftp.sendmail.org.

UnsafeGroupWrites

This option is deprecated. If required, you should now use the GroupWritableForwardFileSafe and GroupWritableIncludeFileSafe arguments for the DontBlameSendmail option.

UseErrorsTo

This option is deprecated. Furthermore, because this option violates RFC 1123, you should avoid using this option. 

O ClientPortOptions=pair,pair              # for the configuration file
-OClientPortOptions=pair,pair              # for the command line
define(`confCLIENT_OPTIONS',`pair,pair')   # for m4 configuration

Addr

Specifies the address mask. The value can be a numeric address in dot notation or a network name. If the pair is omitted, the default is INADDR_ANY, which accepts connections from any network.

Family

Specifies the address family. The key's default is inet for AF_INET. Other values are inet6 for AF_INET6, iso for AF_ISO, ns for AF_NS, and x.25 for AF_CCITT.

Listen

Specifies the size of the listen queue. The key defaults to 10. You should not have to change this default for the Solaris operating environment.

Port

Specifies the name and number of the listening port. The key defaults to smtp.

RcvBufSize

Specifies the size of the TCP/IP send buffer. The key has no default value, which means that no size specifications are automatically made. If the option is set to a value that is greater than zero, that value is used. You should not have to limit the size of this buffer for the Solaris operating environment. 

Modifier

Specifies flags for sendmail:

The h flag uses the name that corresponds to the outgoing interface address for the HELO or EHLO commands, whether it was chosen by the connection parameter or by the default.

The A flag disables AUTH. This flag can also be used with the Modifier key for DaemonPortOptions. Refer to Changes to DaemonPortOptions Option.

The S flag turns off the use of or the offer to use STARTTLS when email is being delivered or is being received.

O DaemonPortOptions=pair,pair              # for the configuration file
-ODaemonPortOptions=pair,pair              # for the command line
define(`confDAEMON_OPTIONS',`pair,pair')   # for m4 configuration 

Name

A new key that specifies a user-definable name for sendmail. This key is used for error messages and for logging. The default is MTA.

Modifier

A new key that specifies values for sendmail that can be listed in a sequence without delimiters. For a list of values, see Table 27–6.

Family

Unless a Family is specified in a DaemonPortOptions option, inet is now the only default. If IPv6 users also want to listen on IPv6 interfaces, they can configure additional sockets into sendmail.cf by adding a Family=inet6 setting to a DaemonPortOptions option.

A

Disables AUTH by overriding the Modifier value of a.

Can be used with the Modifier key for ClientPortOptions. Refer to New ClientPortOptions Option.

C

Does not perform host-name canonification. 

E

Disallows the ETRN command.

O

Ignores the socket if a failure should occur. 

S

Turns off the use or the offer to use STARTTLS when email is being delivered or is being received.

Can be used with the Modifier key for ClientPortOptions.

a

Requires authentication. 

b

Binds to the interface that receives the mail. 

c

Performs host-name canonification. Use this value only in configuration file declarations. 

f

Requires fully qualified host names. Use this value only in configuration file declarations. 

h

Uses the interface's name for the outgoing HELO command.

u

Allows unqualified addresses. Use this value only in configuration file declarations. 

${daemon_addr}

Provides daemon address (for example, 0.0.0.0) 

${daemon_family}

Provides daemon family (for example, inet, and inet6)

${daemon_info}

Provides daemon information (for example, SMTP+queueing@00:30:00) 

${daemon_name}

Provides daemon name (for example, MSA) 

${daemon_port}

Provides daemon port (for example, 25) 

${queue_interval}

Provides queue run interval (for example, 00:30:00) 

O PrivacyOptions=argument                # for the configuration file
-OPrivacyOptions=argument                # for the command line
define(`confPRIVACY_FLAGS',`argument')   # for m4 configuration

goaway

This argument no longer accepts the following flags: noetrn, restrictmailq, restrictqrun, restrictexpand, nobodyreturn, and noreceipts.

nobodyreturn

This argument instructs sendmail not to include the body of the original message in delivery status notifications.

noreceipts

When this argument is set, delivery status notification (DSN) is not announced. 

restrictexpand

This argument instructs sendmail to drop privileges when the -bv option is given by users who are neither root nor TrustedUser. The users cannot read private aliases, .forward files, or :include: files. This argument also overrides the -v command-line option.

O Timeout.keyword=value   # for the configuration file
-OTimeout.keyword=value   # for the command line
define(`m4_name', value) # for m4 configuration

aconnect

0

m4 name: confTO_ACONNECT

Limits the total time to wait for all connections to succeed for a single delivery attempt. The maximum value is unspecified. 

control

2m

m4 name: confTO_CONTROL

Limits the total time that is dedicated to completing a control socket request. 

ident

5s

m4 name: confTO_IDENT

Defaults to 5 seconds—instead of 30 seconds—to prevent the common delays that are associated with mailing to a site that drops IDENT packets. No maximum value is specified.

lhlo

2m

m4 name: confTO_LHLO

Limits the time to wait for a reply from an LMTP LHLO command. No maximum value is specified.

queuereturn

5d

m4 name: confTO_QUEUERETURN

Includes the value now, which immediately bounces entries from the queue without a delivery attempt.

resolver.retrans

varies

m4 name: confTO_RESOLVER_RETRANS

Sets the resolver's retransmission time interval in seconds, which applies to resolver.retrans.first and resolver.retrans.normal.

resolver.retrans.first

varies

m4 name: confTO_RESOLVER_RETRANS_FIRST

Sets the resolver's retransmission time interval in seconds for the first attempt to deliver a message. 

resolver.retrans.normal

varies

m4 name: confTO_RESOLVER_RETRANS_NORMAL

Sets the resolver's retransmission time interval in seconds for all resolver lookups, except the first delivery attempt. 

resolver.retry

varies

m4 name: confTO_RESOLVER_RETRY

Sets the number of times to retransmit a resolver query, which applies to Timeout.resolver.retry.first and Timeout.resolver.retry.normal.

resolver.retry.first

varies

m4 name: confTO_RESOLVER_RETRY_FIRST

Sets the number of times to retransmit a resolver query for the first attempt to deliver a message. 

resolver.retry.normal

varies

m4 name: confTO_RESOLVER_RETRY_NORMAL

Sets the number of times to retransmit a resolver query for all resolver lookups, except the first delivery attempt.