2，配置 mailx
vim /etc/mail.rc

#This is the configuration file for Heirloom mailx (formerly
#known under the name "nail".
#See mailx(1) for further options.
#This file is not overwritten when ‘make install‘ is run in
#the mailx build process again.

#Sccsid @(#)nail.rc 2.11 (gritter) 8/2/08

#Do not forward to mbox by default since this is likely to be
#irritating for most users today.
set hold

#Append rather than prepend when writing to mbox automatically.
#This has no effect unless ‘hold‘ is unset again.
set append

#Ask for a message subject.
set ask

#Assume a CRT-like terminal and invoke a pager.

#Messages may be terminated by a dot.
set dot

#Do not remove empty mail folders in the spool directory.
#This may be relevant for privacy since other users could
#otherwise create them with different permissions.
set keep

#Do not remove empty private mail folders.
set emptybox

#Quote the original message in replies by "> " as usual on the Internet.

#Automatically quote the text of the message that is responded to.
set quote

#Outgoing messages are sent in ISO-8859-1 if all their characters are
#representable in it, otherwise in UTF-8.
set sendcharsets=iso-8859-1,utf-8

#Display sender‘s real names in header summaries.
set showname

#Display the recipients of messages sent by the user himself in
#header summaries.
set showto

#Automatically check for new messages at each prompt, but avoid polling
#of IMAP servers or maildir folders.
set newmail=nopoll

#If threaded mode is activated, automatically collapse thread.
set autocollapse

#Mark messages that have been answered.
set markanswered

#Hide some header fields which are uninteresting for most human readers.
ignore received in-reply-to message-id references
ignore mime-version content-transfer-encoding

#Only include selected header fields when forwarding messages.
fwdretain subject date from to

#For Linux and BSD, this should be set.
set bsdcompat

set [email protected]
set smtp="smtps://smtp.163.com:465"
set [email protected]
set smtp-auth-password=qincexxx
set smtp-auth=login
set nss-config-dir=/etc/pki/nssdb/mail/

3，測試mailx工具是否可以正常發送郵件
echo "test 123456"|mail -v -s "title" [email protected]

4，寫入用戶家目錄下的環境變量文件中，這裏測試的root用戶
vim /root/.bashrc

if [ -f /etc/bashrc ]; then
. /etc/bashrc
fi
echo "$(whoami) login at: $(date) ip address: $(w|sed -n ‘3p‘|awk ‘{print$3}‘)" | mail -s root [email protected]

5，使配置配置文件生效並退出shell終端進行測試
source /root/.bashrc

6，重新登錄測試

Linux服務器用戶登錄郵件告警