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§Ú¥ý»¡©ú¤@¤U¡y§Aª¾¹DSENDMAIL(¤W¡B¤U)¥U¤G¥»®Ñ¦³¦h«p¶Ü?¡z¦]¦¹§Ú­Ì¤£¥i¯à¦bµuµu
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LINUXCONFµ¥¡A°£«D§A­nÅܦ¨¤@­ÓSENDMAILªº±M®a¡A¤~¾¨¶q¨Ï¥Î¤â°Ê¨Ó­×§ï³]©w¡A¦bºô
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¦Ñ°ÝÃD,¥H¤U¦³¤@¨Ç¦Ñ°ÝÃD§Ö­n³Q°Ý¨ìÄê¤F,§Ú¤£ª¾¹D¬°¤°»ò¤H­Ì¤@¹J¨ì°ÝÃD¤£·|¥ý§ä           
howto¡B©Î¬Oºô¯¸¡B©Î¬Obbs(news)¸Ì¥ý«e§O¤H°Ý¹Lªº°ÝÃD¤ÎµªÃD´N¶Ã°Ý

                             
¥H¤U´N/etc/aliaseÀɮר䤺®e»¡©ú:                                     
¥D­n¤À¦¨¨â³¡¥÷,§Q¥Î'¡G'¤À¦¨¨âÃä 
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    ¥ªÃä¡G ¥kÃä  
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           ¥kÃä¥i¯àªº®æ¦¡¡G      
           1. Local Username:¥»¦aªº¨Ï¥ÎªÌ±b¸¹ 
               ex: root: 	panda 
           2. Local Filename:¥»¦aªºÀÉ®×(§¹¾ã¸ô®|) 
               ex: nobody:	/dev/null 
           3. Command       :©R¥O 
               ex: ftphelp:	|/usr/local/bin/sendhelp 
           4. Include File  :¥H¬YÀɮפºªº¤H­û·í§@¦¬¥ó¤H 
              ex: contact:    :include: /etc/mail/mailinglist 
              (­n¥[¤W:include:«á±µ§¹¾ãÀɮ׸ô®|) 
           5. E-Mail Address :»·ºÝªºe-mail¦ì§}(user@domain) 
              ex: root:	panda@ks.edu.tw 
=============================================================       

¹ê§@:             
¤½¥q¦³4­Ó¤H¤À§O¬OA,B,C,D. A¬O¥DºÞ·Q­n¬Ý¨ì©Ò¦³¶i¨ì¤½¥qªº¶l¥ó,¦ÓB,C,D¬O¾­û¥u¯à¦¬¨ì¦Û¤vªº«H             
§@ªk:             
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C: A,C             
D: A,D             
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B: A,B
C: A,C
D: A,D

¤½¥q¦³­Ó³¡¥÷¥ssales,¨ä¤¤¥]§t¤F¤­­Ó¤H,boss,amy,sophie,sherry,sam§Ú­Ì­n¦³¤@­Ó³¡ªùe-mail¦b
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§Y¥i 

sendmail©È¦³¨Ç¤H¦]³]©w¿ù»~²£¥ÍµL½a°j°é,¨Ï«H¥óµL­­¼W¥Í
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   c:  b,a           
²£¥Í¤F¤@­Ó°j°é b©Mc ªº¤¬¬Û¸m´«,¦]¦¹sendmailªº§@ªk¬O·í
«H¥óªÌ©M¦¬°eªÌ¬O¦P¤@­Ó®É·|³Q§R°£,¦Û¤vµLªk°eµ¹¦Û¤v,¤@ºØ§ï¨}
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b: .,c 

 
·í«H¥ó±Hµ¹¬Y¨Ï¥ÎªÌ®É¡Asendmail·|§ä´M¨Ï¥ÎªÌ®a¥Ø¿ý¤Uªº¤@­ÓÀɮ׬°.forward
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¸ÜÁö¦p¦¹,¦³¤@¨ÇISP¦phinet,seednet             
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¦ý­YFTP¨S¦³³QÃö³¬,§A¥i¥H¦bpcºÝ¼g¦n.forward¦A¤W¶Ç¨ì¥D¾÷¤W             
¥»¦aªºUSER¦b«e­±¥[¤@­Ó      ->³oºØ§@ªk¤ñ¸û¦n·|ª½±µ¼g¤J¨Ï¥ÎªÌMAILÀɮפ¤           
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¥æ¥I§Oªºµ{¦¡³B²z¥[¤@­Ó"|µ{¦¡ °Ñ¼Æ"
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a,/b,c,"|/usr/bin/vacation a";

1.¼g¤J¥»¦a¨Ï¥ÎªÌa     
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vacation ¬O¤@ºØ¤H­û©ñ°²®Éemail¦¬«Hªº³B²zµ{¦¡
¥¦·|¨Ï¥Î¨ì.forwardÀɪº³]©w¤@¯ë¤£»Ý¨Ï¥ÎªÌ¤â°Ê³]©w
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1.¦Û°Ê¦^ÂФ@«Ê«H¤º®e¬°¨Ï¥ÎªÌhome¥Ø¿ý¤Uªº.vacation
2.®Ú¾Ú.forwardÂà«Hµ¹¥¦¤H,¤Î¦Û¤v
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¨Ï¥ÎªÌ¦WºÙ,"|usr/bin/vacation ¨Ï¥ÎªÌ¦WºÙ",¨ä¥¦¨Ï¥ÎªÌ;

1.¨Ï¥ÎªÌ¦WºÙ ,¦Û¤v«O¯d¤@¥÷³Æ¥÷
2.|user/bin/vacation ¨Ï¥ÎªÌ¦WºÙ,¦^Âаe¥óªÌ¶l¥ó
3.¨ä¥¦¨Ï¥ÎªÌ,Âà«Hµ¹§O¤H

1. Àɮתº¨ú±o

Vacationªººô¯¸http://vacation.sourceforge.net
2. ¨ä¥D­nÀɮ׬°:
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/usr/bin/vacation	¥D­nµ{¦¡
/usr/bin/vaclook	¬d¬Ývacation.db¸ê®Æ®wµ{¦¡
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.vacation.msg	¦Û°Ê¦^ÂЪº«H¥ó¤º®e
.vacation.db	°O¿ývacationªº­Ó¤H³]©w

¦b¤£¤[¤§«e§Úªºlinux¦øªA¾¹¥X²{¤F°ÝÃD¡A¨Ï¥Îtelnet ip 25¤Î¨ä¥¦ªºport
§¡¬O¤ÏÀ³«D±`ªººC¬Æ¦Ütimeout¡A¦bºô¸ô¤W§ä¤Fµª®×³£»¡¬O¤Ï¸Ñªº°ÝÃD
¥u­n¦b/etc/hosts¥[¤Jip¤Î¦WºÙ´N¥i¥H¤F,¬°¤FÅçÃÒµª®×ªº¯u¹ê©Ê§Ú¤@¦Ó
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1.telnet private ip 25 :¤ÏÀ³«D±`ªººC
2.telnet public ip 25:¥¿±`
3.telnet hostname 25:¥¿±`
4.telnet ¨Ï¥Îprivate ip ªº¬Y¤@¨Çport¥¿±`¬Y¤@¨Ç¤ÏÀ³«D±`ªººC
5.sever  ¤W¦Û§Útelnet§¡¥¿±`

¦A¥hºÊ¬Ýserver¤Wªº¦æµ{µo²{·íclient³s½u®É,server ºÝ¤W·|²£¥Í¤@­Ó¦æµ{
sendmail(startup)¸g¹L«Ü¤[[¤~¶i¤Jsendmail(accept)ªºª¬ºA,¥Ñ©ó¤§«e
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hosts¥i¥H¸Ñ¨M³o­Ó°ÝÃD,¥i¬O¬°¤°»ò©O?¨ì¤F³Ì«á§Ú¦bsendmailªººô¯¸¦b
¤W­±§ä¨ì¤Fµª®×,¤W­±»¡µÛ¤£¤[¤§«ednsªº(root)®Ú¥D¾÷§ïÅܤFprivate ip
ªº³B²z¤è¦¡,¦pªG§Aªºµ{¦¡¨Ï¥Îgethostbyaddress()ªº¨ç¦¡¨Ó¬d¸ßprivate ip
±N¶Ç¦^¤@­Ó¿ù»~¡A¦]¦¹²£¥Í¤F¤@­Ó½wºCªº¦^À³¡A¦]¦¹³o­Ó¼vÅT©Ò¦³¨Ï¥Î
gethostbyaddress()¨ç¦¡ªºµ{¦¡¡A­n¸Ñ¨M³o­Ó°ÝÃD¦p¤U:
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ip  hostname
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192.168.0.1 my1
192.168.0.2 my2 

2.³]©wdns,¾A¦X¤j«¬ºô¸ô ,
ª½±µ³]©w,¦pªG§A¨Ï¥Î192.168.0.ºô¸ô°Ï¬q
redhat7.x¦b/etc/named.conf¤¤¥[¤J
zone "0.168.192.IN-ADDR.ARPA"{
     type master;
     file "/var/named/192.168.0.rev"
}
¦b/var/named·s¼W¤W­±ªºÀɦW192.168.0.rev
$TTL 38400
0.168.192.in-addr.arpa.  IN SOA ¥»¾÷¦WºÙ. ºÞ²zªÌ.¥D¾÷.
(
           ¦~¤ë¤é??: serial
           3H: refresh
           1H: retry
           7D: expire 
           640; default_ttl
           )
0.168.192.in-addr.arpa.   IN   NS  ¥»¾÷¦WºÙ.           
1.0.168.192.in-addr.arpa. IN   PTR  ¹q¸£¦WºÙ1.
2.0.168.192.in-addr.arpa. IN   PTR  ¹q¸£¦WºÙ2. 

1.$TTL¬°¤º©w
2.serial §Ç¸¹¦Û¤v½s¦ý¬O¤@¯ë¬O¥H¦~¤ë¤é+¨â¦ì¼Æ¦r(·sªº­n¤ñªº¤j)
3.refresh
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³o¬Osendmail«Ø¥ß¸ê®Æ®wªº¤u¨ã
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/etc/mail/¤U¦³¤@°ïdbÀÉ,¨ä°ÆÀɦW¬°.db,¨ä¥Î·N¬O¥[³t¸ê®Æªº¦s¨ú
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KEY	VALUE ¬O¥HTABLE¤À¶}
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¥Îªk:
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makemap hash ¥ØªºÀÉ   < ¨Ó·½ÀÉ          #hash ¬O¸ê®Æ®wªº®æ¦¡(btree©Îhash)
makemap hash  access  < mytext          #¥ØªºÀɪº«ü©waccess·|¦Û°Ê¥[°ÆÀɦW¦¨¬°access.db
makemap -v hash access < mytext         #¦pªG­nÆ[¬Ý¥[¤J¸ê®Æªº¹Lµ{¥[-v

¤W­z¤v¸g±N¸ê®Æ¥Ñ¤å¦rÀÉmytextÂন¸ê®Æ®waccess.db 
¦pªG§A·Qª¾¹D¬ÛÃöªºÀɮ׳]©w½Ð°Ñ¦Ò

1. rejected senders
   
©Úµ´À°¦Cªí¨Ï¥ÎªÌ°e«H
¨ä®æ¦¡¥i¥H¬Oºô°ì©Îip
xxx@domainname
domainname
ccc.bbb.ccc.ddd
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2. relay "email from" by IP
   
­ã³ip¦Cªí
¨ä®æ¦¡¥i¥H¬Oip
192.168.0.1
¥i¥H¬O¤lºô¬q


192.168.0.	#192.168.0.0¦Ü192.168.0.254
10.0.	#10.0.0.0 ¦Ü10.0.254.254



3. relay "email from" by name
   
­ã³\¥D¾÷¦WºÙ©Î¬Oºô°ì¦W¦Cªí
¤@¯ë¬O¥»¦a¥D¾÷³B²z¥»¾÷ªººô°ì©Î¬O¥D¾÷

4. relay "email to" by ip or name
   
¦pªGe-mail¬O­n±H¨ì³o­Óip©Î¬Oºô°ìªº±µ¨ü
³]©w³Æ´©¥D¾÷®É­n³]©w½Ð°Ñ¦Ò³Æ´©¥D¾÷

  ³oùاڭ̱Nmailconfªºvirtual domainªº³]©w°Ê§@¤@¤@¥[¥H¸Ñ»¡
  1.©Ò¦³ªºsendmail¥D­nªº³]©w©ñ¦b/etc/mail
  2.§A·s¼WªºµêÀÀºô°ìªº¦WºÙ·|¥[¤J/etc/mail/sendmail.cV
  3.§A·s¼W¤@­ÓµêÀÀºô°ì«á¸Óºô°ìªº©Ò¦³ªº³]©wÀÉ©ñ¦betc/mail/vmail¤U
  4.¦pªG§A·s¼W¤@­ÓµêÀÀpop±b¸¹·|¦b/etc/mail/vmail·s¼W¤T­ÓÀÉ
    aliases.µêÀÀºô°ì¦WºÙ ¨Ò¦pµêÀÀºô°ì¬° vdomain.com  aliases.vdomain.com
    passwd.µêÀÀºô°ì¦WºÙ                              passwd.vdomain.com
    shadow.µêÀÀºô°ì¦WºÙ                              shadow.vdomain.com
  5.µêÀÀºô°ìªº®a¥Ø¿ý¤º©w
    /vmail/ºô°ì¦WºÙ/home/¨Ï¥ÎªÌ¦WºÙ  
   

 ·í§Aªºmail server·í¤F©Î¬O¤Ó¦£µLªk¦^À³®É«ç»ò¿ì©O?
 ¤@¯ëªº·Qªk¬O¥i¦³¥t¤@¥x¥N¦¬¡A¥H¤U´N¬O§Ú­Ì­n»¡¦p¦ó³]©w:
 ³o­Ó³]©w­n¨Ï¥Î¨ìDNS¡ADNS¤¤¦³¤@­Ó³]©w¥s°µMX(¶l¥ó¦øªA¾¹)ªº³]©w
 ¥¦¥i¥H³]©w¬Y¤@ºô°ì©Î¥D¾÷ªº¦¬«H¥D¾÷,§A¥i¥H³z¹L³]©wÅv­­(prior)¥¦¥»¨­
 ¬O¤@­Ó¼Æ¦r,¼Æ¦r·U¤pÀu¥ýÅv·U¤j¨ä½d¨Ò¦p¤U:
 @    mx 5  abc1@mycompany.com
 @    mx 10 abc2@mycompany.com
 @    mx 15 abc3@othercompany.com
 ¤]´N¬O
 @¬O¥»ºô°ì
 5,10,15¬OÀu¥ýÅv
 ¦]¦¹abc1¦³³Ì¤jªºÀu¥ýÅvabc3¦³³Ì¤pªºÀu¥ýÅv
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 ¥N¦¬¬O±Nmail¦¬¤U¨Ó,¦ý¬O³Ì«áÁÙ¬O±NÂà°e¦^abc1