HadoopϵÁУºÔÚLinuxϲ¿Êðhadoop 0.20.1
Á½Ì¨²âÊÔÐé»ú£¬ÏµÍ³ÎªREHL 5.3 x64£¬Õý³£°²×°×îа汾µÄJDK£¬ÕýÈ·ÉèÖÃSSHÎÞÃÜÂëµÇ¼¡£
·þÎñÆ÷Ò»£º192.168.56.101 dev1
·þÎñÆ÷¶þ£º192.168.56.102 dev2
´Óhttp://apache.freelamp.com/hadoop/core/hadoop-0.20.1/ÏÂÔØhadoop-0.20.1.tar.gz£¬°Ñhadoop-0.20.1.tar.gz¿½±´µ½dev1µÄ“/usr/software/hadoop”Ŀ¼Ï¡£µÇ¼dev1Ö´ÐÐÒÔÏÂÃüÁ
# cd /usr/software/hadoop
# tar zxvf hadoop-0.20.1.tar.gz
# cp -a hadoop-0.20.1 /usr/hadoop
# cd /usr/hadoop/conf
ÐÞ¸Ähadoop»·¾³ÅäÖÃÎļþhadoop-env.sh
# vi hadoop-env.sh
Ìí¼ÓÒÔÏÂÄÚÈÝ£º
export JAVA_HOME=/usr/java/jdk1.6.0_16
ÐÞ¸ÄhadoopÖ÷ÒªÅäÖÃÎļþcore-site.xml
# vi core-site.xml
Ìí¼ÓÒÔÏÂÄÚÈÝ£¨¿ÉÒÔ¸ù¾ÝÐèÇó×ÔÐж¨Ò壩£º
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!-- Put site-specific property overrides in this file. -->
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://dev1</value>
<description>The name of the default file system. Either the literal string "local" or a host:port for DFS.</description>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/usr/hadoop/tmp</value>
<description>A base for other temporary directories.</description>
</property>
<property>
<name>dfs.name.dir</name>
<value>/usr/hadoop/filesystem/name</value>
<description>Determines where on the local filesystem the DFS name node should store the name table. If this is a comma-delimited list of directories then the name table is replicated in all of the directories, for redundancy. </description>
</property>
<property>
<name>dfs.data.dir</name>
<
Ïà¹ØÎĵµ£º
Service Discovery Protocol(SDP)ÌṩһÖÖÄÜÁ¦£¬ÈÃÓ¦ÓóÌÐòÓз½·¨·¢ÏÖÄÄÖÖ·þÎñ¿ÉÓÃÒÔ¼°ÕâÖÖ·þÎñµÄÌØÐÔ¡£
·þÎñ·¢ÏÖÐÒé(SDP»òBluetooth SDP)ÔÚÀ¶ÑÀÐÒéÕ»ÖжÔÀ¶ÑÀ»·¾³ÖеÄÓ¦ÓóÌÐòÓÐÌØÊâµÄº¬Ò⣬·¢ÏÖÄĸö·þÎñÊÇ¿ÉÓõĺÍÈ·¶¨ÕâЩ¿ÉÓ÷þÎñµÄÌØÕ÷¡£SDP¶¨ÒåÁËbluetooth client·¢ÏÖ¿ÉÓÃbluetooth server·þÎñºÍËüÃǵÄÌØÕ÷µÄ·½·¨¡£ ......
1. ½ø³ÌÊÇʲô?
Ò»¸ö½ø³Ì¾ÍÊdzöÓÚÖ´ÐÐÆÚµÄ³ÌÐò, °üÀ¨:¿ÉÖ´ÐгÌÐò´úÂë(´úÂë¶Î), ´ò¿ªµÄÎļþ, ¹ÒÆðµÄÐźÅ, ÄÚºËÄÚ²¿Êý¾Ý, ´¦ÀíÆ÷״̬, µØÖ·¿Õ¼ä, Ò»¸ö»ò¶à¸öÖ´ÐÐÏß³Ì, µ±È»»¹°üÀ¨ÓÃÀ´´æ·ÅÈ«¾Ö±äÁ¿µÄÊý¾Ý¶Î, µÈµÈ.
2. ʲôÊÇÏß³Ì?ËüºÍ½ø³ÌµÄ¹ØÏµÊÇʲôÑùµÄ? Ïß³ÌÔÚLINUXÖоßÌåÊÇÔõôÑùʵÏÖµÄ?
ÊÇÔÚ½ø³ÌÖлµÄ¶ÔÏó ......
Ò»£®Ìî¿ÕÌ⣺
1. ÔÚLinuxϵͳÖУ¬ÒÔÎļþ·½Ê½·ÃÎÊÉ豸 ¡£
2. LinuxÄÚºËÒýµ¼Ê±£¬´ÓÎļþ/etc/fstabÖжÁȡҪ¼ÓÔØµÄÎļþϵͳ¡£
3. LinuxÎļþϵͳÖÐÿ¸öÎļþÓÃi½ÚµãÀ´±êʶ¡£
4. È«²¿´ÅÅÌ¿éÓÉËĸö²¿·Ö×é³É£¬·Ö±ðΪÒýµ¼¿é ¡¢×¨ÓÃ¿é ¡¢ i½Úµã±í¿é ºÍÊý¾Ý´æ´¢¿é¡£
5. Á´½Ó·ÖΪ£ºÓ²Á´½Ó ºÍ ·ûºÅÁ´½Ó¡£
6. ³¬¼¶¿é°üº¬ÁËi½Úµã±í ......
¹ØÓÚread(...)·µ»ØÖµµÄÕýÈ·Åжϣºp30
File I/O µÄ read(...)º¯ÊýÓ÷¨£º
ÓÐÎÊÌâµÄ´úÂ룬ֻÅжϷµ»ØÖµÎª-1µÄÇé¿ö¡£
unsigned long word;
ssize_t nr;
/* read a couple bytes into 'word' from 'fd' */
nr = read (fd, &word, sizeof (unsigned long));
if (nr == -1)
/* error */
Indeed, a call to read( ) ca ......
1. java ... > log.out
½«Java³ÌÐòÊä³ö ±£´æµ½ log.out Îļþ
2. java .... >>log.out
ÓëÉÏÒ»¸ö²»Í¬£¬Õâ¸öÊÇ×·¼Óµ½Îļþ£¬¶ø²»»á¸²¸ÇÔÓÐÊä³ö.
3. java .... >>log.out 2>&1
ÔÚJavaÀï(ÆäËûÓïÑÔÒ²Ó¦¸ÃÒ»Ñ ......