Linux

Linux Ethernet Bonding – load balancing / active-passive

This is a notice in the topic of Linux Ethernet Bonding with two ethernet NIC

The case:
There is a server with two ethernet NIC. They are going to be set as either load balancing or active-passive mode.

  1. For load balancing (round-robin) – mode = 0, this is the default, transmitting packets in order from the first available slave through the last, for load balancing and fault tolerance.
  2. For active-passive – mode = 1, Only one of the bond slaves is used, and the others act as stand-by mode. Once the active one failure, after particular time period (miimon=xxx), the stand-by one will take over and resume the network connection.

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[Linux Raid] mdadm raid 1 resizing partition

In order to resize the raid file system from small capacity to larger one, we should reset the raid size and file system size to new setting.
Here are two simple case studies to increase and reduce raid size.
Case 1: Increase the size of /dev/md4 from 4GB to 8GB

  • pre-check the file system
  • increase the raid capacity
  • resize file system capacity
  • pro-check
  • mount and use

Case 2: Reduce the size of /dev/md4 from 8GB to 6GB

  • umount the file system
  • pre-check
  • reduce the file system capacity
  • reduce the raid capacity
  • pro-check
  • mount and use

Reference: HowToForge

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經SSH翻牆@CityU

今日要上cs4280, 但正直要試 linux mdadm raid 1 disk expandion 先不可以經lab 去連vnc 相關的port. 那即時上網找找ssh 番牆的方法. google 大佬真係勁, 首幾個post 就已答到我問題 Jamyy's Weblog - PuTTY - SSH Tunnel 運用備忘 提到用ssh tunnel 的方法. 用Dynamic Tunnel…

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Dell 2950 Dual E5420 + CentOS + KVM + Eth0 Bridge Mode

今日代人入手 Dell 2950 , 拎完番來即"操"佢. 玩完佢個DRAC5 後,  就即安OS 安過VMware ESXi (但用Client 連線失敗), 之後都係直接安CentOS 5.4 64bit. 再玩Virtual Machine - KVM. 先係安個XP, 再安VISTA, 再安CentOS. 但發現Win XP 運行時係會拎個分俾佢用的CPU Full Loading. 但CentOS 又冇事. 找一找RH…

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Exim is taking apache port

近日同個客CHECK機，　佢話個APACHE 時唔時就會死, 連唔上. 一CHECK 之下, 竟然係MAIL SERVER -EXIM 拎了個port 80 來做野. 真係奇怪. 經過一番google 及check 機後, 得出的結論係: SERVER 軟件中, MOD_PHP / 其他plugin 在CALL mail() 的時候, 會因為apr 內的BUG 導致死HTTPD 而且會自動替換角色. 由原先HTTPD 所持有的PID…

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[HOWTO] Squid proxy authentication using ncsa_auth helper

其實都俾人ORDER 咗好耐要做的事來了. 但遲遲未做起.. 今次一次過搞好VNC & PROXY AUTHENTICATION, 心情也不錯! Following are included by default in most squid and most Linux distros: => NCSA: Uses an NCSA-style username and password file. =>…

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