Fix the RFC 822-related bug in Cisco IOS

From CT3

Embedded Event Manager (EEM) in IOS releases up to 12.4(15)T2 and 12.2(33)SRC does not insert an empty line required by RFC 822 (and subsequent SMTP-related RFCs) between the message header and the message body in e-mails sent with the action mail EEM applet command (bug details; available to registered CCO users). This bug might manifest itself if you send e-mails from the router to an SMTP MTA that stricter in checking RFC compliance as the Unix sendmail program and its derivatives. E-mail user agent receiving the ill-formed e-mail message might display the e-mail body in the subject line.

To fix this problem, you can manually insert CRLF combination in the e-mail body generated with the action mail command with the \015\012 escape sequence. For example, to send an e-mail every time an interface changes its status, use the following EEM applet:

Please check the Send e-mail from EEM applet page for additional detailed explanations of various EEM environment variables and action mail command parameters.

event manager applet InterfaceUpDown
 event syslog occurs 1 pattern "UPDOWN" period 1
 action 1.0 info type routername
 action 2.0 mail server "$_mail_smtp" to "$_mail_rcpt" →
    from "$_info_routername@$_mail_domain" subject "Interface state change" →
    body "\015\012$_syslog_msg"

The non-printable characters entered in the EEM action mail command with the escape sequence are not escaped when displayed in the router configuration, resulting in a configuration that is hard to read/copy.

The workaround has been provided by Gerald Kowalsky