Peter Luk's Blog

Microsoft live mesh

Just tried Microsoft live mesh (http://www.mesh.com). It is a service to sync files between different computers (most importantly, it works with MacOSX). It provide a tool to operate right on your desktop just like a folder and a web interface as well. Moreover, you can also invite your friends to read/edit files in that folder too. Another way of collaboration. I can use this service to share full resolution photos among friends which is not possible with web hosting services.

I have tried something similar before (foldershare) but the feature and performance is not that good. Sometimes you must wait long time for your files to be sync. (It is acquired by ms and become part of the windows live, may be it is better now).

Let’s see this new service can fulfill my needs or not and stay on my desktop.

zoomit from microsoft technet

ZoomIt is screen zoom and annotation tool for technical presentations that include application demonstrations.

I found this tool quite handy to zoom out small text or during presentation. Much convenient that the Magnifier builtin in Vista. Moreover, MacOSX 10.5 also provide similar function in the accessibility control panel

You can download it from MS technet

Using linux ethernet bridge to counter arp posioning

arp poisoning within LAN (usually a client infected with a virus/Trojan and it spoof the default router mac addr and take the network down or by ddos the default router with arp) is one of attack that is a bit difficult to defense. Subnetting the network into much more smaller part can reduce the impact of it. ie., separating your servers from your clients. However, there’s no protection between clients and once the default router mac addr is poisoned in the client subnet, the subnet housed those clients is still down. Moreover, resubnetting the network involves high hidden management costs as well. The other method is that one can deploy switches with anti-arp poisoning feature (Cisco 35XX switch or above with DHCP snooping and arp inspection). This providescomplete protection but involving replacement of a no. of edge switches. Moreover, those clients must be using DHCP to make it work (or you need to enter their mac addr manually into the switch…)

Another much cheaper method is to segment your LAN into two parts. One is a trusted zone where ur router, servers and clients you would like to be separated from others (say your admin machine) are placed. The other is an untrusted zone where your clients will be placed. These two segments will be connected using a Linux bridge. arp reply/request will be allowed from the trusted to untrusted zone but on the other direction they will be inspected and only reply from registered pair of ip/mac are allowed.

This can be easily accomplished in a Linux bridge using ebtables:

#!/bin/bash
#eth0 : connected to vlanA1 (trusted)
#eth1 : connected to vlanA2 (untrusted)

PATH="/usr/local/sbin"

ebtables -F
ebtables -X
#allow arp reply of below pair only from eth1
ebtables -A FORWARD -i eth1 -p arp --arp-ip-src 192.168.99.100--arp-mac-src aa:bb:cc  -j ACCEPT
#allow arp request from eth1
ebtables -A FORWARD -i eth1 -p arp --arp-opcode 1 -j ACCEPT
#drop all other arp reply from eth1
ebtables -A FORWARD -i eth1 -p arp -j DROP

Installation of Adobe CS3 on Vista x64: A @!#$% journery

I have spent nearly 2 days to install this software on my Vista machine. The installer program is really written badly and it really wasted me a lot of time.

First, I had to uninstall the original Adobe CS2 on my machine and really really unlucky, I think I have got a bad installation disk with a corrupted file. Therefore, at the very first installation, I could only got the shared components installed and all others failed. The most annoying thing was that there’s no informative messages reported from the installer. It only said that there’s some components failed to install. Moreover, during the lengthy installation, I had to close all the browsers which made me could not use the machine to do other things except waiting. (I had another machine in my office and I could work on the other machine). OK fire up the firefox and go the adobe KB to search for solution. Oh my god, there’s a tone of problems and solutions about CS3 installation so I had to do some analysis before picking up any solutions. At last I decided to check the log of the installer first. It was a around 3MB zip file located in C:\Program Files (x86)\Common Files\Adobe\Installers. However when the log file was uncompressed, it was around 26MB and this choked the notepad (cannot read it) and notepad++ (not responding whenever I want to search). At last I used grep (from cygwin) and successfully finding some clues of the problem. When I used the keyword “error” to grep the log, I found that a log entry telling that the installer could not read the AdobeDeviceCentralAll1.cab. However, when I navigated to that file and opened it, it could be opened. OK, I copied the whole DVD to local HD, uninstall and reinstall, still got the same result. I replaced the installation disk and used the new disk to try to install the CS3 on a XP machine and the installation completed without any problem. I determined the original disk was having problem and the new disk should be alright.

Second, I used this new disk to install. This time, all the components installed without problem except Acrobat 8.0. OK, I did the troubleshooting as before and tried to grep the log file to see if there’s any clues of the problem. This time the installer complained as below :

OK, from the log, it said that it could not access the C:\Program Files (x86)\Common Files\Adobe\Acrobat\ActiveX directory. It should be the stuff left by the previous unsuccessful installation. I tried to remove it but the system returned permission denied (oc I had run the explorer under administrator rights). OK, boot to safe mode to delete it, still no luck. OK boot using UBCD, still couldn’t. Oh my god, why Adobe protect such directory like a virus and and made it undeletable. At last I boot back the system and used the below procedures to remove it :

– Right click on the “ActiveX” folder
– Select “Properties”
– Go to the “Security” tab
– Click on the “Advanced” button
– In the “Permissons” tab hit the button “Edit”
– Check the box called “Replace all existing inheritable permissions on all
descendants with inheritable permissions from this object”
– Hit “Ok” on all of the three open windows.
– Delete the folder!

There’s a directory left out by Adobe CS2 in c:\adobe\acrobat 7.0 \adobe\activeX. I used the same method to remove it again.

After removing the C:\Program Files (x86)\Common Files\Adobe\Acrobat\ActiveX directory, I would be able to install back the Acrobat 8.0

Really don’t understand why the installation of the CS3 is so buggy and causing so many problems. BTW, I have tried to install it on a clean install of Vista (without any application installed), it could be installed without a glitch. This only tell us that the success of CS3 installation can be greatly affected by the applications and services already installed on a system. Moreover, the error handling and reporting of the installer is really suck.

mount iso/bin image on Vista

I use Virtual CloneDrive (http://www.slysoft.com/en/virtual-clonedrive.html), should be free with trojian

綠豆仔現況

呢棵綠豆仔之前D葉黃哂, 俾phyllis節枝浸根, 變咗棵全新嘅綠豆仔, 希望佢今次唔會咁快黃啦.

Core i7 920 overclock超頻

用Core i7 920嘅最主要原因, 當然係因為佢可以輕鬆超頻. 如果唔係佢得2.66Ghz, 真係搵鬼買佢.

Config :

1. Core i7 920 2.66Ghz with stock cooler (HK $2320)

2. Asus P6T Deluxe V2 (HK $2390)

3. Kingston DDR3 1333Mhz 2GBx3 (HK $760)

4. Inno GTX 260+ Gold (HK $1299)

5. Seagate 1TB 7200.12 x2 (HK $1500)

6. LG DVD-RW (HK $170)

7. 3R K-100 case (HK $295)

8. CoolMaster M620 620W PSU with cable management (HK $825)

9. Installation ($150)

Total : $9709

一開始就試超上3.8Ghz

係windows 7到行埋prime95嘅tortune test都冇問題, 但係因為係用stock cooler, core temp跳到九十幾度, 平時就成五十幾度. 因為我部機會行7X24, 所以上網研究過後, 覺得3.33Ghz係最適合長期用嘅, 佢係最低嘅速度唔駛加電壓. 平時都係48C, full load 就89C