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in Debian-based systems apt-get could be limited to the specified bandwidth in kilobytes using the apt configuration options(man 5 apt.conf, man apt-get). I'd quote man 5 apt.conf:
"The used bandwidth can be limited with Acquire::http::Dl-Limit which accepts integer values in kilobyte. The default value is 0 which deactivates the limit and tries uses as much as possible of the bandwidth..."
"HTTPS URIs. Cache-control, Timeout, AllowRedirect, Dl-Limit and proxy options are the same as for http..."
-T = traceroute
-V = verbose
--tr-stop = exit when target is reached
-n = don't do reverse lookups (faster)
-2 = udp
-p 53 = destination port 53 (dns), change to your needs
Useful when trying to debug a network with complex routing rules and/or multiple gateways.
find the files locked by rcs utility
If you spot a dubious looking cp command running you can use this command to view what is being copied and to where.
1234 is the PID of the cp command being passed to the lsof utility.
3r.*REG will display the file/directory that is being read/copied.
4w.*REG will display the destination it is being written to.
An alternative which does not require to be root
This one is a little bit easier for those of us that aren't always root.
after that, you can launch bash script in your usb drive in FAT32.
I used this to mass install a lot of perl stuff. Threw it together because I was feeling *especially* lazy. The 'perl' and the 'module' can be replaced with whatever you like.
kill all the (-y) from the interface eth1, not touching the legitimate server with 00:11:22:33:44:55
Add the BackTrack repositories to your Debian based GNU/Linux distribution. Thanks to http://it-john.com/home/technology/linux-technology/add-back-track-4-repo-to-ubuntu/
Will limit the amount of CPU time Grooveshark the greedy yet useful Adobe Air app will have.
Leaves the UI lagging a little, but crucially does not ruin the audio.
This command works at least in 9.04+
 download the CISCO VPN client for linux: http://tuxx-home.at/archives/2007/09/24/T15_26_49/
 apply this ciscpo VPN patch: http://bit.ly/linux_vpn_patch
[*] use command to start client
[*+1] After copying your profile file to /etc/opt/cisco-vpnclient/Profiles, connect using
vpnclient connect TORVPN-TCP
Quick and dirty way to disable the Ubuntu notifications that can be quite annoying. It prevent the notify-osd to start so you need to logout Gnome or kill it by hand to take effect.
When you right click a text box in Firefox and you have installed a few dictionaries you'll see a loooong list of spellcheckers. Most of them are duplicated (symlinks). This command deletes de duplicates and reduces the list.
"The -b (background) option tells sudo to run the given command in the background." -- after it asks you for the password in the foreground.
Take advantage of sudo keeping you authenticated for ~15 minutes.
The command is a little longer, but it does not require X (it can run on a headless server).
By default sudo 'remembers' password for a few minutes, so that you do not need to re-enter password for a series of sudo commands that might follow within a short time duration.
However, sometime you might want sudo to instantly 'forget' the password.
(Next sudo command will need you to reenter the password)
Credit: I first learned this while listening to one of the 'tuxradar' podcast.
look at /boot/grub/menu.lst for somethig like:
## additional options to use with the default boot option, but not with the
## e.g. defoptions=vga=791 resume=/dev/hda5
## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(verbose mode) vga=775 debug
# altoptions=(console mode) vga=ask
# altoptions=(graphic mode) quiet splash
# altoptions=(recovery mode) single
vga=(decimal value) is framebuffer mode
If you update youtube-dl from the repos, it becomes out-of-date quickly. Luckily, it can auto-update.
sudo is optional, but to find out about all files, it is nice, or else run as superuser, ie: su -c 'du -sm * | sort -n'
We sometimes need to change kernel parameters by echoing the file . This needs root privilege and if we do it using sudo like this , it fails
sudo echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
-bash: /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: Permission denied
We can achieve this with the tee command by just doing sudo without logging as root user