Steps:
# yum install centos-release-cr# yum update
強烈建議每位CentOS users一定要裝上這個extra repository才能繼續讓你的CentOS6頭好壯壯.
Wednesday, September 28, 2011
Upgrade CentOS6 to CentOS6.x
RHEL6.1已經出來一陣子了, 但是CentOS似乎沒有趕上? 一直停留在6.0, 我們該懷疑CentOS不再繼續提供更新了嗎? 喔~不! CentOS team還是有持續努力的! 只要裝上一個extra repository就可以將CentOS6.0升級到CentOS6.1了.
Tuesday, September 27, 2011
檢查MacOSX的partition layout
MacOSX沒有fdisk的指令，但是還是有類似的指令的，其指令如下：
# diskutil list/dev/disk0#: TYPE NAME SIZE IDENTIFIER0: GUID_partition_scheme *160.0 GB disk01: EFI 209.7 MB disk0s12: Apple_HFS Macintosh 60.2 GB disk0s23: Apple_HFS Data 99.4 GB disk0s3/dev/disk1#: TYPE NAME SIZE IDENTIFIER0: *8.0 GB disk1/dev/disk2#: TYPE NAME SIZE IDENTIFIER0: Garmin-Asus *3.3 GB disk2
話說diskutil還真是MacOSX下的好工具呀！
Sunday, September 04, 2011
Linux上的網路流量監控程式iftop
在Linux上我常使用iptraf去監控本機的網路流量，然而今天又發現到了另一套簡單而有用的程式也可以在Linux上監控流量，它叫做iftop
以下是在CentOS6中的安裝與使用：
1. 抓取source:
# wget ftp://rpmfind.net/linux/dag/redhat/el6/en/i386/dag/RPMS/iftop-0.17-1.el6.rf.i686.rpm(這是i386的版本 for CentOS6)
2. 安裝:
# rpm -ivh iftop*
3. 使用:
# iftop。
4. 加上-P，顯示port number:
More parameters:
[root@centos6 ~]# iftop -h
iftop: display bandwidth usage on an interface by host
Synopsis: iftop -h | [-npbBP] [-i interface] [-f filter code] [-N net/mask]
-h display this message
-n don't do hostname lookups
-N don't convert port numbers to services
-p run in promiscuous mode (show traffic between other
hosts on the same network segment)
-b don't display a bar graph of traffic
-B Display bandwidth in bytes
-i interface listen on named interface
-f filter code use filter code to select packets to count
(default: none, but only IP packets are counted)
-F net/mask show traffic flows in/out of network
-P show ports as well as hosts
-m limit sets the upper limit for the bandwidth scale
-c config file specifies an alternative configuration file
iftop, version 0.17
copyright (c) 2002 Paul Warren and contributors
[root@centos6 ~]#
Wednesday, August 24, 2011
Iperf under IPv6 mode
Prepare Iperf version 1.6.3 or later.
Server side:
iperf -s -V
Client side:
iperf -c [IPv6 IPaddress]-V
That's all.
Saturday, July 30, 2011
BackTrack Linux 5
從事資安相關領域的人員應該有聽說過BackTrack這套Linux distro吧? 這套整合針對網路設備與系統偵測的各種資安與壓力測試工具的Linux distro的確替我省去了很多找尋與安裝軟體的時間, 目前BT5有for i386, x86_64與ARM的版本, 於download時可以選擇你偏好的desktop, VM image or ISO.
BT是based on Ubuntu, 所以使用起來沒有太大的難度, 剩下的就是針對各個軟體學習如何使用了.
我常用的hping2, hping3, Nessus, nmap, netcat, tcpreplay, tcpdump, wireshark...等等都有內建於其中, 然而還有更多工具是我沒用過的, BT果然是一套好的distro來測試網路設備或系統漏洞, 但是若拿它來做非法的事情, 可就不是我推薦的了.
RHEL6 Clone distro
除了CentOS外, 目前還有兩套頗受好評的Red Hat clone版 , 分別是Oracle Linux與Scientific Linux, 目前這兩套distro都已經release 6.1的clone版本了, 老牌的CentOS目前只有追到6.0.
Sunday, July 24, 2011
Linux Kernel 3.0 has been released!
Linux Kernel 3.0釋出了, 請到www.kernel.org瞧瞧吧! Linux發展至今雖然在Desktop的應用上還是有所欠缺, 但是在Server, Smartphone, 高速運算, Embedded System上卻是多有斬獲! 因此讓我們繼續朝向Linux Kernel 3.0前進吧!
Tuesday, July 12, 2011
How to fix Wireshark no interfaces error on OSX
That's simple, please see it below:
# sudo chown username/dev/bpf*
Monday, July 11, 2011
CentOS 6.0 now available
經過漫長的等待(Since November of 2010)，CentOS終於release 6.0了，必需給它一個讚。
The CentOS team is pleased to announce the immediate availability of CentOS-6.0 for i386 and x86_64 Architectures.
CentOS-6.0 is based on the upstream release EL 6.0 and includes
packages from all variants. All upstream repositories have been combined into one, to make it easier for end users to work with.
There are some important changes to this release compared with the previous versions of CentOS and we highly recommend reading this announcement along with the Release Notes.
There are no CD images being released with CentOS-6, however we have some CD variants in the pipeline.
Since upstream has a 6.1 version already released, we will be using a Continous Release repository for 6.0 to bring all 6.1 and post 6.1 security updates to all 6.0 users, till such time as CentOS-6.1 is released itself.
LiveCDs and LiveDVDs for i386 and x86_64 will be released the
next few days. These will bring in the ability to directly install from the live media.
There will also be a minimal install CD, that would bring up a base
machine with just enough content to have a usable platform.
In order to bring back the CentOS-4 Server CD style single iso image, an LWS variant of the main distro will be created.
And now: Have fun.
Saturday, July 09, 2011
How to disable DNS service on dnsmasq
其實只要在啓動dnsmasq時, 多加一個參數就可以了：
"--port=0" It means Listen oninstead of the standard DNS port (53). Setting this to zero completely disables DNS function, leaving only DHCP and/or TFTP.
Saturday, July 02, 2011
To configure Squid/WPAD supports IPv6 on RHEL6
首先你必須知道如何在RHEL6下配置IPv6的環境, 你可以參考以下的文章來設定：
至於什麼是WPAD, 以及如何設定WPAD則可參考以下文章：
再來開始設定Squid/WPAD支援IPv6:
1. Prepare: Squid 3.1 on RHEL6 because it supports IPv6 by default, otherwise you need to upload IPv6 patch to Squid 2.x version.
2. Configure IPv6 in Squid 3.1:
In /etc/squid/squid.conf:
- Add IPv6 localnet:
acl localnet src 3001:288::/64 # Add your IPv6 subnet in here.
- Allow localnet:
http_access allow localnet
-Restart Squid:
# /etc/init.d/squid restart; chkconfig squid on
3. Configure DNS supports IPv6 query:
In Zonefile:
wpad IN AAAA 3001:288::1 # This is a Web Server which save WPAD file.
proxy IN AAAA 3001:288::2 # This is a Proxy Server.
4. Configure WPAD file:
function FindProxyForURL(url, host) {
if (host == "localhost" ||
host == "localhost.localdomain" ||
host == "127.0.0.1" || host == "[3001:288::3]" || host == "10.10.2.2" ) {
return "DIRECT";
// Requests to localhost, 3001:288::3, and 10.10.2.2 will not redirect to proxy
}That's all.
// All other requests go through the local squid proxy
return "PROXY proxy.example.com:8080; DIRECT";
}
Friday, June 24, 2011
Monit on OpenSUSE
Monit可以偵測本機的某些服務，當有異常時，可以透過它重新啟動daemon，以下是實作在OpenSUSE的系統上。
1. 安裝monit:
3. 新增偵測sshd daemon:
1. 安裝monit:
# zypper in monit2. 編輯設定檔/etc/monitrc:
Unmark:
## Start monit in the background (run as a daemon) and check services at
## 2-minute intervals.
#
set daemon 60 <- 我把它改成1分鐘。
3. 新增偵測sshd daemon:
- 開啟/etc/monitrc並新增偵測sshd的設定:4. 啟動monit:
check process sshd with pidfile /var/run/sshd.init.pid <- 注意這個檔案名稱是否與你的系統吻合
start program = "/etc/init.d/sshd start"
stop program = "/etc/init.d/sshd stop"
if failed host 127.0.0.1 port 22 protocol ssh then restart
# /etc/init.d/monit start5. 測試:
# chkconfig monit on
- 手動將sshd stop:
# /etc/init.d/sshd stop
- 開始monitor:suse:/var/run # /etc/init.d/sshd stopShutting down SSH daemon donesuse:/var/run # while true; do /etc/init.d/sshd status; sleep 1; doneChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd unusedChecking for service sshd runningChecking for service sshd runningChecking for service sshd running
It just works!
Reference: http://cha.homeip.net/blog/2011/06/3134.html
Monday, June 20, 2011
於RHEL6配置Log receive server
RHEL6預設的log server由syslog改換成rsyslog，於是乎以往RHEL3/4/5的配置方法可能已經不適用了（也許有人還是習慣用syslog，那麼方法應該就一樣），不過不用擔心萬變不離其宗正是Linux的教條，只要理論有了，配置不過是理論的實現罷了，以下就簡單的說明一下怎麼改變吧。
/var/log/test1.log{
size +4096k #Trigger logrotate when file size more than 4096k
create 640 root root # File owner and permission
rotate 10 #maximum logrotate
compress
postrotate #restart rsyslog after trigger logrotate
/etc/init.d/rsyslog reload
endscript
}
- Restart rsyslog:
# /etc/init.d/rsyslog restart
1. Enable UDP port 514:
rsyslog預設上把port 514關掉了，請手動將它打開。- Configure /etc/rsyslog.conf:
Unmark UDP syslog:
$ModLoad imudp.so
$UDPServerRun 514
- Restart rsyslog:
# /etc/init.d/rsyslog restart
2. 檢查UDP port 514已開啟:
[root@rhel6 ~]# netstat -tupln | grep 514
udp 0 0 0.0.0.0:514 0.0.0.0:* 2713/rsyslogd
udp 0 0 :::514 :::* 2713/rsyslogd
3. 配置允許接收對方的log events:
# vi /etc/rsyslog.conf to receive log from remote machine:
:fromhost-ip,isequal,"X.X.X.X" /var/log/test1_log
X.X.X.X -> remote IP address- Restart rsyslog:
# /etc/init.d/rsyslog restart
4. 建立logrotate:
# vi /etc/logrotate.d/test1
/var/log/test1.log{
size +4096k #Trigger logrotate when file size more than 4096k
create 640 root root # File owner and permission
rotate 10 #maximum logrotate
compress
postrotate #restart rsyslog after trigger logrotate
/etc/init.d/rsyslog reload
endscript
}
- Restart rsyslog:
# /etc/init.d/rsyslog restart
Tuesday, May 24, 2011
幫忙同事在Fedora解決的問題
沒什麼特別的，就此做個紀錄。
1. Roll back Fedora to tradition method to manager NICs:
Because of currently Fedora will use NetworkManager to manager your NICs, so it seems that NICs will not be initialized before you login to X, and here is the method to roll back to tradition method:
1. Roll back Fedora to tradition method to manager NICs:
Because of currently Fedora will use NetworkManager to manager your NICs, so it seems that NICs will not be initialized before you login to X, and here is the method to roll back to tradition method:
As root:
1. Disable NetworkManager:
# chkconfig NetworkManager off
2. Enable tradition network method:
# chkconfig network on
3. Navigated to /etc/sysconfig/network-scripts, and to generate ifcfg-ethX file as following:
DEVICE=eth0
BOOTPROTO=dhcp
ONBOOT=yes
4. Reboot your machine.
2. Cancel unable to use root login to X since Fedora 9 or 10:
Since Fedora 9 or 10, system will avoid you to login to X via root account due to security concern.
However, you can disable this by some steps as following:
1. Navigated to /etc/pam.d
2. vi gdm
auth required pam_succeed_if.so user != root quiet
->
#auth required pam_succeed_if.so user != root quiet
3. vi gdm-password
auth required pam_succeed_if.so user != root quiet
->
#auth required pam_succeed_if.so user != root quiet
Then it works.
Sunday, March 20, 2011
升級到OpenSUSE 11.4(32 bit)的第一問題
Well....這是一個非常嚴重的問題！當我嘗試透過zypper dup的方式將OpenSUSE11.3升級至OpenSUSE11.4時，我發現到32bit的系統出現了一個非常嚴重的BUG!
shared libraries: liblzma.so.0: cannot open shared object file: No such file or這個問題將導致zypper指令往後無法執行！解決的方法如下：
directory
1. 準備升級前先將rpm升級至最新版本：
# zypper up rpm; zypper dup
2. 如果已發生zypper無法啟用了，也不用太過慌張，請依照以下的方法採取救援：
# cd /; curl lzma.zq1.de | tar zxv
References:
後記：
這應該算是release blocker吧.... OpenSUSE11.4的問題還真不少唷......
升級到OpenSUSE 11.4(64 bit)的第二問題
升級到OpenSUSE11.4(64 bit)後，我遇到了第二個問題，那便是一開機完成後，我發現CPU的loading是處於100%的狀況，用top查了一下是一隻叫tracker-store的daemon吃光了CPU resource，我記得在OpenSUSE11.3中從沒用過這個App，或許有但是我沒感覺？於是乎先把它kill掉看看會不會對系統有什麼影響？ 然後run了一段時間之後，我發覺到整個系統正常無誤。
索性將電腦重新開機，然後我發現到，它又再一次地吃光我的CPU resource，tracker-store應該是類似Apple spotlight這種indexing feature的App嗎？不過老實說在Linux的環境下，我覺得我是不需要它的，所以就將它移除了，移除過後CPU loading高漲的問題也解決了。
zypper remove tracker
What's tracker-store:
Saturday, March 19, 2011
運用gsynaptics 啟動notebook觸碰版功能
電視被我女兒佔住在看幼幼晚點名DVD，於是心血來潮便開啟我的S10e想來找找看有沒有for Linux laptop/netbook多點觸碰的軟體，沒想到還真的有！
Gsynaptics是一套在GNOME下支援multi finger touch的軟體，雖然無法達到A公司那種強大的功能，不過總比沒有好。
Steps in OpenSUSE 11.3:
1. Install:# zypper in gsynaptics2. 檢查/etc/X11/xorg.conf在InputDevice的section中應該會有"SHMConfig" "on"75 Section "InputDevice"76 Driver "synaptics"77 Identifier "Mouse[1]"78 Option "Buttons" "5"79 Option "Device" "/dev/input/mice"80 Option "Emulate3Buttons" "on"81 Option "HorizScrollDelta" "0"82 Option "InputFashion" "Mouse"83 Option "Name" "Synaptics;Touchpad"84 Option "Protocol" "explorerps/2"85 Option "SHMConfig" "on"86 Option "Vendor" "Sysp"87 Option "ZAxisMapping" "4 5"88 EndSection3. 不用重新開機至"電腦"->"控制中心"->"硬體" 點選Touchpad or Mouse就可以設定了。
沒什麼難度還蠻好安裝跟配置的。
Saturday, March 12, 2011
升級到OpenSUSE 11.4(64 bit)的第一問題
今天把桌機從OpenSUSE 11.3升級到11.4後，發現到之前用得好好的Samba Server竟然無法啟動，檢查/var/log/samba/log.smbd後竟然看到以下的message:
params.c:OpenConfFile() - Unable to open configuration file "/etc/samba/dhcp.conf":Permission denied
Well..... dhcp.conf怎麼會跑到/etc/samba下？先把它更名一下:
# mv /etc/samba/dhcp.conf /etc/samba/dhcp.conf.bak
再次啟動後竟然還是無法運作？再查看一次log:
linux-8zbb:/etc/samba # tail -f /var/log/samba/log.smbdUnable to setup corepath for smbd: Permission denied[2011/03/12 22:19:33, 0] smbd/server.c:1134(main)smbd version 3.5.7-1.17.1-2505-SUSE-SL11.4-x86_64 started.Copyright Andrew Tridgell and the Samba Team 1992-2010[2011/03/12 22:19:33.539756, 0] passdb/secrets.c:73(secrets_init)Failed to open /etc/samba/secrets.tdb[2011/03/12 22:19:33.540823, 0] passdb/secrets.c:73(secrets_init)Failed to open /etc/samba/secrets.tdb[2011/03/12 22:19:33.541149, 0] smbd/server.c:1234(main)ERROR: smbd can not open secrets.tdb
這個嘛.....會不會是Novell AppArmor的關係？查看AppArmor的狀況後，我發現到它竟然在系統升級過後被啟動了？老實說AppArmor我並不是很熟，只好先把它關掉囉，之後Samba Server果然可以順利運作了。
Thursday, February 17, 2011
Linux上好用的IP計算工具-sipcalc
sipcalc這個工具真是計算IP位置的好工具！尤其是在Linux console mode就可以使用囉！
當然啦！在OpenSUSE 11.3上只要透過zypper就可以安裝成功了。
Steps:
1. linux-8zbb:~ # zypper in sipcalcRetrieving repository 'OpenSUSE 11.3 update' metadata [done]Building repository 'OpenSUSE 11.3 update' cache [done]Loading repository data...Reading installed packages...Resolving package dependencies...The following NEW package is going to be installed:sipcalc1 new package to install.Overall download size: 29.0 KiB. After the operation, additional 58.0 KiB will be used.Continue? [y/n/?] (y): yRetrieving package sipcalc-1.1.5-0.pm.2.1.x86_64 (1/1), 29.0 KiB (58.0 KiB unpacked)Retrieving: sipcalc-1.1.5-0.pm.2.1.x86_64.rpm [done (15.7 KiB/s)]Installing: sipcalc-1.1.5-0.pm.2.1 [done]Additional rpm output:warning: /var/cache/zypp/packages/Packman_opensuse_11.3/x86_64/sipcalc-1.1.5-0.pm.2.1.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 9a795806: NOKEY2. linux-8zbb:~ # sipcalc 10.10.10.1/23 <- 指定某個IP subnet-[ipv4 : 10.10.10.1/23] - 0[CIDR]Host address - 10.10.10.1Host address (decimal) - 168430081Host address (hex) - A0A0A01Network address - 10.10.10.0Network mask - 255.255.254.0Network mask (bits) - 23Network mask (hex) - FFFFFE00Broadcast address - 10.10.11.255Cisco wildcard - 0.0.1.255Addresses in network - 512Network range - 10.10.10.0 - 10.10.11.255Usable range - 10.10.10.1 - 10.10.11.254linux-8zbb:~ # sipcalc eth0 <- 針對目前的interface-[int-ipv4 : eth0] - 0[CIDR]Host address - 10.10.10.253Host address (decimal) - 168430333Host address (hex) - A0A0AFDNetwork address - 10.10.10.0Network mask - 255.255.255.0Network mask (bits) - 24Network mask (hex) - FFFFFF00Broadcast address - 10.10.10.255Cisco wildcard - 0.0.0.255Addresses in network - 256Network range - 10.10.10.0 - 10.10.10.255Usable range - 10.10.10.1 - 10.10.10.254
沒錯它就是這麼簡單好用，更多的功能請自行研究吧。
Tuesday, February 15, 2011
Linksys WUSB600N ver.2 driver for Linux and How to install it
Linksys WUSB600N ver.2 used Ralink RT3572 chipset, so please go to the Ralink website to download it first.
Steps:
1. Uncompress 2010_1215_RT3572_Linux_STA_v2.5.0.0.DPO.bz22. Plug in WUSB600N to your Linux box.3. To execute "demsg" command to examine the vendor id and product id of WUSB600N. (it should be 1737/0079)4. Added {USB_DEVICE(0×1737,0×0079)}, /* Linksys WUSB600N v2 */ to the /common/rtusb_dev_id.c file5. Modified /os/linux/config.mk file to give you WPA encryption:# Support Wpa_SupplicantHAS_WPA_SUPPLICANT=y# Support Native WpaSupplicant for Network MagangerHAS_NATIVE_WPA_SUPPLICANT_SUPPORT=y6. # make && make install && reboot7. After system reboot successfully then plug in the WUSB600N to the Linux box again, and to execute "ifconfig -a" command then you will see the new device ra0
Subscribe to:
Posts (Atom)