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.

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.

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 IDENTIFIER

0: GUID_partition_scheme *160.0 GB disk0

1: EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh 60.2 GB disk0s2

3: Apple_HFS Data 99.4 GB disk0s3

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: *8.0 GB disk1

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: Garmin-Asus *3.3 GB disk2

話說diskutil還真是MacOSX下的好工具呀！

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 ~]#