盛輝上門電腦維修IT Support

mac 10.5 freeze when waking form hibernation with VM running parallels

shing fai it consult — Sun, 11 Sep 2011 15:59:01 +0000

OS: Mac 10.5.8
Parallels version: Parallels desktop 7 for MAC
Mac hibernate mode: 5
Symptom: mac freeze when waking from hibernate mode with VM running

Possible solution:
Change hibernate mode to 1

1.Check the current setup
pmset -g | grep hibernatemode

2. Change the sleep mode setting
sudo pmset -a hibernatemode 1

—-hibernate mode info——
0 – Old style sleep mode, with RAM powered on while sleeping, safe sleep disabled, and super-fast wake.
1 – Hibernation mode, with RAM contents written to disk, system totally shut down while “sleeping,” and slower wake up, due to reading the contents of RAM off the hard drive.
3 – The default mode on machines introduced since about fall 2005. RAM is powered on while sleeping, but RAM contents are also written to disk before sleeping. In the event of total power loss, the system enters hibernation mode automatically.
5 – This is the same as mode 1, but it’s for those using secure virtual memory (in System Preferences -> Security).
7 – This is the same as mode 3, but it’s for those using secure virtual memory.

dd-wrt /CoovaAP recovery howto

shing fai it consult — Thu, 30 Jun 2011 09:00:35 +0000

Following methods tried in linksys wrt54g and tp link w741nd:

1. Hard Reset (“30/30/30 reset”) if configuration messed up
i. hold the reset button while power on or 30 seconds
ii. disconnect the power while continuing hold the reset button for 30 seconds
iii. while still holding it in, plug in the power again and keep holding the reset button for another 30 seconds
The router will back to default setting, i.e. 192.168.1.1

2. Firmware restore
My wrt54g got “no space left” so i decided to restore the firmware
i. telnet/ssh to the router and run the following commands to break the router, it will restore the router back to default setting:
mtd erase linux
reboot
ii. assign an static ip to your notebook e.g. 192.168.1.10
iii. open a command prompt and type: ping -t 192.168.1.1
iv. open another command prompt and type: tftp -i 192.168.1.1 put dd-wrt.xxxx.bin
do not press the enter
v. unplug and plug the router power supply
vi. as soon as the ping command got response again, press enter in the tftp windows

sample output:
C:\wrt>tftp -i 192.168.1.1 put dd-wrt.v24_mini_wrt54g.bin
Transfer successful: 3019776 bytes in 7 seconds, 431396 bytes/s

C:\wrt>tftp -i 192.168.1.1 put openwrt-wrt54g-squashfs.bin
Transfer successful: 2774016 bytes in 11 seconds, 252183 bytes/s

tips: find out the router mac address and add arp
arp -s 192.168.1.1 aa-bb-cc-dd-ee-ff

http://www.dd-wrt.com/wiki/index.php/Recover_from_a_Bad_Flash#Linksys_Firmware

http://www.dd-wrt.com/wiki/index.php/Reset_And_Reboot#Hard_Reset_.28.2230.2F30.2F30_reset.22.29

http://wiki.openwrt.org/doc/howto/generic.flashing.tftp?s[]=tftp

real time traffic analysis in Linux

shing fai it consult — Fri, 27 May 2011 07:17:21 +0000

tools:
ibmonitor for real-time traffic consumed: http://ibmonitor.sourceforge.net/

jnettop for real-time traffic visual analysis : http://download.fedora.redhat.com/pub/epel/4/i386/repoview/jnettop.html

tcpdump for real-time packet capture
iptables for block unwanted traffic

tcpdump howto:
1. dump traffic without port 22 and write it to file log.cap

tcpdump -i eth0 not port 22 -n -w log.cap

2. tcpdump for dummies: http://www.alexonlinux.com/tcpdump-for-dummies

iptables in centos howto:
1. block outgoing traffic to specific ip
-A OUTPUT -d 10.79.2.145 -j DROP

2. block incoming traffic from specific ip
-A RH-Firewall-1-INPUT -s 10.79.2.145 -j DROP

Bash script to find an delete specific user process

shing fai it consult — Wed, 13 Apr 2011 04:45:01 +0000

for x in `ps aux|grep imap|grep emily|awk ‘{print $2}’`; do kill -9 $x;done

install virtualbox in centos 5.5

shing fai it consult — Fri, 11 Mar 2011 06:29:09 +0000

1. get the virtual box software

2. make necessary system changes

yum install dkms

useful commands

shing fai it consult — Fri, 11 Mar 2011 05:51:59 +0000

To perform groupinstall:

# yum groupinstall ‘KDE’

To get the available and installed groups:
# yum grouplist

Multi -boot for Windows and Linux

1.In Linux,

dd if=/dev/hda2 of=/linux.bin bs=512 count=1

2. copy the linux.bin file to Windows c:\

3. In Windows, add following in the boot.ini

c:\linux.bin=”Linux”

rsync remote backup tips

shing fai it consult — Sun, 06 Mar 2011 07:47:57 +0000

Task : Copy file with space from a local computer to a remote server

Copy file from ‘/home/itconsult/Maildir/.e-mail 2009-2010′ to a remote server (192.168.1.198) under the directory /home/itconsult/Maildir

/usr/bin/rsync -avHS --delete '/home/itconsult/Maildir/.e-mail 2009-2010' root@192.168.1.198:'/home/itconsult/Maildir/' > /var/log/rsynclog/itconsult 2>&1 &

Problem: If seeing the errors below in rsunc corn job, it may be caused by too many files to be synced:

rsync: writefd_unbuffered failed to write 4 bytes: phase “unknown” [sender]: No route to host (113)
rsync: connection unexpectedly closed (1106082 bytes received so far) [sender]
rsync error: error in rsync protocol data stream (code 12) at io.c(434)

Soultion:

manually run the rsync command from the console for the affected user or directory
rerun the corn job

電腦維修送4GB USB手指

shing fai it consult — Thu, 03 Mar 2011 04:35:42 +0000

為慶祝盛輝科技新的電腦維修中心成立，恵顧盛輝科技電腦維修服務，

可獲贈4GB USB手指乙條!!

維修中心地址: 香港筲箕灣道283號海景廣場9樓05室

熱線: 3495 3389

電郵: info@itconsult.hk

盛輝電腦維修中心 – HK$168自攜電腦維修，不成功不收費

shing fai it consult — Wed, 23 Feb 2011 10:18:05 +0000

為慶祝盛輝科技新的電腦維修中心成立，現在提供特別優惠 —

HK$168自攜電腦維修，不成功不收費。

維修中心地址: 香港筲箕灣道283號海景廣場9樓05室

熱線: 3495 3389

電郵: info@itconsult.hk

flush netbios cache

shing fai it consult — Fri, 11 Feb 2011 06:45:24 +0000

nbtstat -R

nbtstat -c

nbtstat -RR