错误详情：

# m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
*** ERROR: FEATURE() should be before MAILER()
*** MAILER(`local') must appear after FEATURE(`always_add_domain')*** ERROR: FEATURE() should be before MAILER()
*** MAILER(`local') must appear after FEATURE(`allmasquerade')*** ERROR: FEATURE() should be before MAILER()

　　

解决办法：

按照提示，编辑 /etc/mail/sendmail.mc 文件，将 FEATURE() 放到 MAILER() 之前：

更改

dnl #
dnl # Default Mailer setup
MAILER_DEFINITIONS
MAILER(`local')dnl
MAILER(`smtp')dnl

dnl # Masquerading options
FEATURE(`always_add_domain')dnl
MASQUERADE_AS(`tumblr.3sd.me')dnl
FEATURE(`allmasquerade')dnl
FEATURE(`masquerade_envelope')dnl

　　为

dnl #

dnl # Masquerading options
FEATURE(`always_add_domain')dnl
MASQUERADE_AS(`tumblr.3sd.me')dnl
FEATURE(`allmasquerade')dnl
FEATURE(`masquerade_envelope')dnl

dnl # Default Mailer setup
MAILER_DEFINITIONS
MAILER(`local')dnl
MAILER(`smtp')dnl

　　

 

 

 

 

 

 

 

 

 

 

 

 

 

 

摘自：https://mozillazg.com/2013/02/linux-fix-sendmail-configuration-error-feature-should-be-before-mailer.html