kvm qcow2 resize

qemu-img resize vm.qcow2 +20GB apt-get install libquestfs-tools or apt-get install ./libguestfs-tools_1.32.2-4ubuntu2_amd64.deb cp vm.qcow2 vm.qcow2.org virt-resize --expand /dev/sda1 vm.qcow2.org vm.qcow2.qcow2 virt-filesystems --long -h --all -a vm.qcow2.qcow2

how to remove samba printer icon 移除印表機圖示

#]vi /etc/samba/smb.conf

[globa]

disable spoolss = yes

VSFTP Configuration - vsftpd 安裝設定

1. 安裝:
RPM Requierment: vsftpd-2.0.5-16.el5

]#yum install vsftpd

2 設定:

2.1 設定vsftpd.conf:
]# vi /etc/vsftpd/vsftpd.conf

###begin of file###

##使用stand alone 方式啟動vsftpd daemon
listen=YES

#不允許 anonymous login
anonymous_enable=NO

#允許local端使用者登入
local_enable=YES

#允許檔案修改寫入
write_enable=YES

#設定新增檔案權限umask (目錄755檔案644)
local_umask=022

#允許顯示操作目錄訊息
dirmessage_enable=YES

#確認使用20 port 傳輸資料
connect_from_port_20=YES

##log 相關設定
#允許同時使用 vsftpd log及 xferlog
dual_log_enable=YES
#log timestamp 使用系統時間
use_localtime=YES
#xferlog log設定, 僅記錄檔案傳輸訊息.
xferlog_std_format=YES
xferlog_enable=YES
xferlog_file=/var/log/xferlog
#記錄所有vsftp user動作log
log_ftp_protocol=YES
#log路徑
vsftpd_log_file=/var/log/vsftpd.log

##使用change root 將使用者鎖在家目錄中
chroot_local_user=YES

##啟動禁止login的帳戶清單
#法一
userlist_enable=YES
#啟動清單中名單禁止
userlist_deny=YES
userlist_file=/etc/vsftpd/user_list
#法二
#使用系統pam認證, 設定禁止名單
pam_service_name=vsftpd

##啟動chroot功能
chroot_list_enable=YES
#若chroot enable, 此為允許列出上層目錄名單
#若chroot disable, 此為不允許列出上層目錄名單
chroot_list_file=/etc/vsftpd/chroot_list
####其選項, # mask 起來即可.

###end of file ####

2.2 設定pam的vsftpd檔:

]# vi /etc/pam.d/vsftpd

###begin of file##
#%PAM-1.0
session optional pam_keyinit.so force revoke
auth required pam_listfile.so item=user sense=deny file=/etc/vsftpd/ftpusers onerr=succeed
auth required pam_shells.so
auth include system-auth
account include system-auth
session include system-auth
session required pam_loginuid.so
###end of file###

3 啟動測試:

3.1 啟動vsftpd:

]# /etc/init.d/vsftpd start

確認是否有錯誤訊息.

3.2 建立帳號:

]# useradd username
建立使用者username, 預設家目錄為/home/username.
]# passwd username
設定username密碼.

3.3 登入測試:

]# ftp 127.0.0.1
Connected to 127.0.0.1.
220 (vsFTPd 2.0.5)
530 Please login with USER and PASS.
530 Please login with USER and PASS.
KERBEROS_V4 rejected as an authentication type
Name (127.0.0.1:root): username
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp>

ok!

3.4 檢查vsftp log:

]# tail -f /var/log/vsftpd.log
Fri Oct 16 14:35:17 2009 [pid 1461] FTP response: Client "127.0.0.1", "530 Please login with USER and PASS."
Fri Oct 16 14:35:23 2009 [pid 1461] FTP command: Client "127.0.0.1", "USER username"
Fri Oct 16 14:35:23 2009 [pid 1461] [username] FTP response: Client "127.0.0.1", "331 Please specify the password."
Fri Oct 16 14:35:25 2009 [pid 1461] [username] FTP command: Client "127.0.0.1", "PASS "
Fri Oct 16 14:35:25 2009 [pid 1460] [username] OK LOGIN: Client "127.0.0.1"
Fri Oct 16 14:35:25 2009 [pid 1462] [username] FTP response: Client "127.0.0.1", "230 Login successful."

ok!

mysql replication setup

實作版本
OS: CentOS 5.3
mysql : 5.1.37

實作目標:

Slave server 資料與 Master server 同步.

設定步驟:

1. 修改 Master Server my.cnf 檔:
#vi /etc/my.cnf
(預設路徑)

[mysqld]
.
.
server-id = 1 #設定id(與slave server區別)

log-slave-updates #啟動覆寫機制

log-bin=dba-master-bin #設定repilation binlog 檔名

存檔跳出後 restart mysql


2. 設定mysql replication 的帳號權限:
#mysql -uroot -p
(登入mysql console)
mysql> grant replication slave on *.* to userrepl@'172.16.%'identified by 'password';
( 帳號 userrepl 密碼 password, 允許172.16.0.0/16的區段連線 )
mysql> flush privileges;
(使帳號權限生效)

3. Master Server 的 lock DB 與dump DB:

3.1 lock DB:
#mysql -uroot -p
( 登入mysql console)
mysql> flush tables with read lock;
(lock db 確保來源檔案在dump的過程中不會再異動)

3.2 查看master log position資訊:

mysql> show master status\G;
*************************** 1. row ***************************
File: dba-master-bin.000005
Position: 845
Binlog_Do_DB:
Binlog_Ignore_DB:
1 row in set (0.00 sec)
ERROR:No query specified

(上面資訊把binlog的檔名:dba-master-bin.000005及位置:845記下來)

3.3 dump DB:
( system console)
#mysqldump -uroot -p --all-database --master-data > ALL_DB.sql
( 將lock中的DB全部dump到ALL_DB.sql)
再把ALL_DB.sql 傳送到slave server上

4. 修改 Slave Server my.cnf 檔:

#vi /etc/my.cnf
(預設路徑)

[mysqld]
.
.
server-id = 2 #設定id(與master server區別)


存檔跳出後 restart mysql

5. Store DB file:

#mysql -uroot -p < ALL_DB.sql ( 將master 的sql檔 store進slave server)


6. Slave mysql setting:

#mysql -uroot -p ( 登入slave mysql console)
mysql> CHANGE MASTER TO
MASTER_HOST='172.16.1.2', ( 示範的master server IP 位置)
MASTER_USER='userrepl',
MASTER_PASSWORD='password',
MASTER_LOG_FILE='dba-master-bin.000005',
MASTER_LOG_POS=845;

mysql> slave start;

( 啟動replication )

7. unlock master db:

回到master server 的mysql console

mysql>unlock tables;
(讓db可以正常寫入)


8. 檢查replication是否正常:

到slave server的mysql console

mysql>show slave status\G;

*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event .
.
.
Last_Errno: 0
Last_Error: ( 沒有錯誤訊息, 正常運作中 )
.
.

如果發生幾個不重要的query錯誤造成停止,
可使用下面命令跳過該query, 繼續運作replication.

mysql>slave stop; (先停止replication)
mysql>SET GLOBAL SQL_SLAVE_SKIP_COUNTER = 1; (跳過的query數)
mysql>slave start; (重啟replication)

新增 swap - CentOS, Fedora, RHEL

1. 新增swap檔案, 例1024Mb的swap空間:

#dd if=/dev/zero of=/swapfile bs=1024 count=1048576

新增 / 下面 swapfile 檔 count= bs * 1024

2. format swap 檔案:

#mkswap /swapfile

3. 啟動與停止 swap:

啟動
#swapon
停止
#swapoff

4. 設定/etc/fstab, 開機時自動mount swap 區塊
#vi /etc/fstab
設定一:
/dev/sda1 swap swap defaults 0 0
/swapfile swap swap defaults 0 0
設定二:
/swapfie swap swap noatime 0 0

5.確認swap是否有啟動

1.#top
2.#free
3.#cat /proc/swap

CentOS, Fedora snmp 設定

1. 使用rpm安裝.

1.1. yum 指令:
#yum install net-snmp

1.2. 設定snmpd.conf

#vi /etc/snmp/snmpd.conf ( 預設路徑 )
寫入
rocommunity public
即可:wq存檔離開,
(此法如果防火牆未開, 任何主機皆可查詢的到你)

CentOS VNC

1.start kdm
#/etc/init.d/xfs start ( important !!!)

1.1kdm
edit option in file /etc/X11/xdm/kdmrc
[Xdmcp]Enable=1
#netstat -tunlp (check listen port shows following)
tcp 0 0 0.0.0.0:6000 0.0.0.0:* LISTEN
5920/Xtcp 0 0 :::6000 :::* LISTEN
5920/Xudp 0 0 :::177 :::*

2.vnc setting

#su "username"#vncpasswd (setting a password for vnc)
clean all words in file/home/"username"/.vnc/xstartup
#exit ( return to root )
#vi /etc/sysconfig/vncservers ( change configure for vnc login user )VNCSERVERS="2:"username""
VNCSERVERARGS[2]="-geometry 800x600 -query localhost"
(2 = port )
#/etc/init.d/vncserver start (start vnc )
ok!

3.vnc start command
#vncserver :3 (start,3 = port )
#vncserver -kill :3(stop)

modify /root/.vnc/xstartup
[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid greyvncconfig -iconic &xterm -geometry 80x24+10+10 -ls -title $VNCDESKTOP Desktop" &
#gnome desktopgnome-session &