Ordinarily, when sendmail sends error notification mail, it expects that error notification to be successfully delivered. Upon occasion, error mail itself will bounce or fail too. This is called a "double-bounce" situation. Prior to V8.8, sendmail would notify postmaster if error notification failed. But this might not be the best solution in all cases. Consider, for example, a site that has a sitewide postmaster and several departmental postmasters. In such situations, double-bounce mail should probably go to the sitewide postmaster. Beginning with V8.8 sendmail , the DoubleBounceAddress option can be used to define who gets double-bounce mail: O DoubleBounceAddress= addr configuration file (V8.8 and later) -ODoubleBounceAddress= addr command line (V8.8 and later) define(`confDOUBLE_BOUNCE_ADDRESS',` addr') mc configuration (V8.7 and later) Here, addr is of type string and is a comma-separated list of one or more email addresses. If addr is missing, the following error is printed and the option is ignored: readcf: option DoubleBounceAddress: value required If the entire option is missing, the default becomes postmaster . If sendmail is unable to send double-bounce mail to addr , it logs the following error: cannot parse addr The DoubleBounceAddress option is not safe. If specified from the command line, it can cause sendmail to relinquish its special privileges. |