Cisco Cisco Email Security Appliance C190 ユーザーガイド
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Cisco AsyncOS 8.5 for Email User Guide
Chapter 9 Using Message Filters to Enforce Email Policies
Message Filter Examples
Detect Looping Filter
This filter is used to detect, stop, and determine what is causing, a mail loop. This filter can help
determine a configuration issue on the Exchange server or elsewhere.
determine a configuration issue on the Exchange server or elsewhere.
Note
By default, AsyncOS automatically detects mail loops and will drop messages after 100 loops.
External_Loop_Count:
if (header("X-ExtLoop1")) {
if (header("X-ExtLoopCount2")) {
if (header("X-ExtLoopCount3")) {
if (header("X-ExtLoopCount4")) {
if (header("X-ExtLoopCount5")) {
if (header("X-ExtLoopCount6")) {
if (header("X-ExtLoopCount7")) {
if (header("X-ExtLoopCount8")) {
if (header("X-ExtLoopCount9")) {
notify ('joe@example.com');
drop();
}
else {insert-header("X-ExtLoopCount9", "from
$RemoteIP");}}
else {insert-header("X-ExtLoopCount8", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount7", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount6", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount5", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount4", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount3", "from $RemoteIP");}}
else {insert-header("X-ExtLoopCount2", "from $RemoteIP");}}
else {insert-header("X-ExtLoop1", "1"); }