My Dell laptop wasn't able to use an external monitor after a week's vacation. The symptoms were: No response when pressing Fn+F8 to swtich displays. "No signal" on external monitor. Bring up "Screen Resolution" dialog, only one monitor is avaiable. Click "Advanced settings" in "Screen Resolution" dialog, Adapter Type displays "VgaSave". There's no "Display adapters" section in Device Manager . Solution: re-install the video display driver. My laptop came with Nvidia GPU so I reinstalled the Nvidia driver. Download the driver pack from Dell. The Windows 7 CAB file is about 1GB, which indludes all kinds of drivers.

Use the expand command to extract files from a .cab file: expand [-r] source [destination] [-d source.cab ... Option Description [-r] Renames expanded files. [destination] Specifies where files are to be expanded. If source is multiple files and -r is not specified, destination must be a directory. destination can consist of a drive letter and colon, a directory name, a file name, or a combination of any of these. [-d source.cab] Displays a list of files in the source location. Does not expand or extract the files. [-f:files] Specifies the files in a cabinet (.cab) file that you intend to expand. You can use wildcards (* and ?). source.cab Specifies the files to expand. source can consist of a drive letter and colon, a directory...

To identify the display driver info with the DirectX Diagnostic Tool included in Widnows 7 and Vista: Bring up the "Run" dialog with the Win button Type dxdiag and press Enter. Click the Diaplay tab.

Install usb.essentials . Package usbutils is optional. # opkg update # opkg install kmod-usb2 # opk... Install usb printer support: # opkg install kmod-usb-printer Install p910nd print server: # opkg install p910nd Edit /etc/config/p910nd : config p910nd option device /dev... Configure firewall to allow port 9100 ( /etc/config/firewall ): # Allow printer con... If clients are connecting from wan then the first line should be: option src wan Enable automatic start of print server when router boots: #/etc/init.d/p910nd enable Restart router: # reboot

Contrary to the DD-WRT router database , the Belkin F5D7231-4 v2000 cannot be flashed with TFTP . When I followed the TFTP procedures, I always got TTL=64 , never TTL=100 or TTL=128 , which is supposed to indicate that the router TFTPd is ready. I got network timeout when I tried to send the bin file anyway. The right way to flash the Belkin F5D7231-4 v2000 is to use the binary and Sercomm Utility provided by eko. Simply: Put the router in upgrade mode: unplug router, press reset button and keep it pressed while plugging in the power. Release it when lan leds turn off. Power and Connected led must blink . start the Sercomm Utility select the network interface connected to the router select...

Use IO redirection to swap stdout and stderr : $ prog 3>&1 >&2 2>&3 3>&-

Nmap port scan against host 10.2.1.3 , with TCP SYN scan ( -sS ), OS detection ( -O , capital O, not zero) and verbose output ( -v ): nmap -v -sS -O 10.2.1.3 If ping is blocked, add switch -PN : nmap -v -sS -O -PN 10.2.1.3 Shortcut option -A for version detection, Nmap Scripting Engine with the default set of scripts, remote OS detection, and traceroute (equivalent to: -sV -sC -O --traceroute ): nmap -A 10.2.1.3

There's no file for OpenWRT syslog. Instead, syslog is a fixed size buffer in memory. Use logread to look at syslog: root@OpenWrt:/# logread -h logread: invalid opt... To tail the log: root@OpenWrt:/# logread -f

VirtualBox creates/uses a network adapter named vboxnet0 on the host, when a VM network adapter is connected as "host-only". As the VM starts, VirtualBox assigns the IP address 192.168.56.1 to vboxnet0 on the host. The VM DHCP client grabs the IP address 192.168.56.101 from the VirtualBox DHCP server. Connectivity is limited between the VM and the host - unless you configure NAT and IP forwarding on the host. For OpenWRT, if the DHCP client is not started automatically: #/sbin/udhcpc -i br-lan -p /var/run/udhcpc.pid -s ...

To check a command exists on PATH: Use the return code of which : which some_command &>/dev/null [ $? -eq 0 ] || ... For bash, use type -P : type -P some_command &>/dev/null && echo "ome_comm... or check_path() { if ! type -P $1 &> /dev/...