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Frequently Asked Questions

A.1\. [see the message "421 no adequate servers" in my, what's causing this?](/momentum/3/3-reference/
A.2\. [How can I run two or more Momentum instances concurrently?](/momentum/3/3-reference/3-reference-faq#faq.running.multiple.instances)
A.3\. [I see error messages saying "errno=24" (on linux), "nropen too low," or "Could not set nofiles high enough!" in my What do they mean and how can I prevent this?](
A.4\. [When I say:](/momentum/3/3-reference/3-reference-faq#faq.sieve.array.after.variable)




I see the message "421 no adequate servers" in my, what's causing this?

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This occurs when Momentum is unable to determine a suitable MX when attempting to deliver mail to a particular domain. There are two probable causes for this situation:

  • DNS resolution is broken.

  • The remote site is employing firewall rules which drop traffic from your IP address.

The cause can be determined via the console:

ecelerity> dig
ecelerity> domain

If the output indicates that there are no MXs for the domain, then the problem is likely DNS related. Check that your /etc/resolv.conf is correct, and that the nameservers it references are in working order.

If the output lists one or more MXs then the cause is likely due to a connectivity problem. You verify this by attempting to manually connect to the remote machine using telnet 25 . You can also use the the swaks tool.

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How can I run two or more Momentum instances concurrently?

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If you want to run two or more Momentum instances concurrently on a single machine, you need to make some adjustments to the various instance-specific configuration options.

This requires that each instance uses its own configuration file. So the first thing you need to do is to get a separate configuration file for your new instance. Let's call it ecelerity1.conf. You need to modify or add the following settings in ecelerity1.conf (This example is based on linux, changes on other operating systems should be similar):


ESMTP, ECSTREAM, Control and other listeners should each be configured to use distinct IP addresses and/or port numbers, as they can't both bind to the same ports on the same IPs.

The Control_Listener used for ec_console connections should have a different Unix domain socket for each instance.


SNMP listens on by default, even if you have no SNMP specific configuration in ecelerity.conf. You should change the port number used by the new instance:

  State = enabled
  Address =
  Community = "public"

Each Momentum instance must have its own spool directory. The following snippet in your ecelerity1.conf will change the spool base directory:

SpoolBase = /var/spool/ecelerity1


Since version 2.0, Momentum maintains a pidfile that can be used by other processes to determine if the instance is running; therefore, each instance must have its own pidfile.

Pidfile = /var/run/


Momentum stores persistent summary and Sieve counter information in the masterdb_file.

masterdb_file = /var/log/ecelerity1/ecdb


If you want to arrange for each Momentum instance to start at system boot time, you might want to copy and modify the ec_ctl script, so that you have one copy per instance. Let's copy /opt/msys/ecelerity/bin/ec_ctl to /opt/msys/ecelerity/bin/ec_ctl1 and modify the copy. Change the following two lines:




Make sure the CONTROL parameter matches what you have configured for your Control_Listener in ecelerity1.conf.


While they are not strictly required to be instance-specific, you will usually want to make sure that you're logging to a separate set of log files for each instance. This is simply a matter of configuring your logging modules appropriately:

ec_logger "ec_logger1" {
  mainlog = /var/log/ecelerity1/
  paniclog = /var/log/ecelerity1/
  rejectlog = /var/log/ecelerity1/

If you do configure a separate log directory, you might also want to arrange for the logs to be rotated. Our Linux packages drop a maintenance script into /etc/cron.d that launches ec_rotate for this purpose. It's a trivial matter to adjust it to rotate the logs for your second log directory.

You're now ready to start your ecelerity1 instance using the following invocation:

# /opt/msys/ecelerity/bin/ec_ctl1 start | |



I see error messages saying "errno=24" (on linux), "nropen too low," or "Could not set nofiles high enough!" in my What do they mean and how can I prevent this?

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These errors happen when the Momentum process has hit either the per-process system limit for maximum open file descriptors or the Server_Max_Outbound_Connections limit configured in ecelerity.conf.

Consult your system documentation for further information on changing the per-process open file descriptor limit, or see “Operating System Specific Preparation” for recommended settings specific to your operating system.

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When I say:

$local = envelope :localpart "from";
if ec_test :is $local ["foo1", "foo2"] {
  ec_action 550 "no foos allowed";

Why do I get the Sieve error "syntax error near token COMMA"?

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The Sieve parser has no way of telling a hash dereference like $local["foo1"] from a regular variable followed by an array like $local ["foo1"], so when it sees a variable followed by an open bracket, it always assumes that it's seeing a hash dereference. As a result, once it gets to the comma in $local ["foo1", "foo2"] it thinks this is invalid syntax (which it is, for a hash dereference). To work around this, you can substitute the variable into a string:

$local = envelope :localpart "from";
if ec_test :is "${local}" ["foo1", "foo2"] {
  ec_action 550 "no foos allowed";


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