How to set network proxy from command line in Ubuntu

You might need to do this if your network settings dialog box crashes as I've seen on Ubuntu 13.10:

gsettings set org.gnome.system.proxy autoconfig-url http://myserver/myconfig.pac

gsettings set org.gnome.system.proxy mode auto

This is how I found out the settings:

$ for key in $(gsettings list-keys org.gnome.system.proxy); do echo $key = $(gsettings get org.gnome.system.proxy $key); done

autoconfig-url = 'http://myserver/myconfig.pac'
ignore-hosts = ['localhost', '127.0.0.0/8']
mode = 'auto'
use-same-proxy = false

It doesn't have to be a .pac file, ours is .dat.

(source)

How to fix ntpdate

# set 'server' value in config to the correct ntp date server on your network
$ sudo vim /etc/ntp.conf

# force update (1.2.3.4 is your ntp date server)
$ sudo /etc/init.d/ntpd stop
$ sudo /usr/sbin/ntpdate 1.2.3.4
$ sudo /etc/init.d/ntpd start


# check it worked (offset should be < 10)

$ ntpq -pn
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 1.2.3.4            6.7.8.3      3 u    6   64    1    3.902   -0.216   0.001
 1.2.3.5            6.7.8.4      3 u    5   64    1    1.753    0.048   0.001

Why doesn't smbclient work?

Symptoms:
You can mount a NetApp 'shared drive' using the mount program fine.
But if you try to browse it using smbclient, you get this error when it fails to connect:
session setup failed: NT_STATUS_MORE_PROCESSING_REQUIRED

Cause:
A bug in Ubuntu 11.04

Workaround:
Change your hostname to a short string, without any hypens (dashes) in it!

(copy)

Use lighttpd as a proxy-pass server

$HTTP["host"] =~ "made.up.hostname" { # hostname you want to create
    $SERVER["socket"] == ":1234" { # port you want to create

        server.errorlog      = "/var/logs/madeup/lighttpd-error.log"
        accesslog.filename   = "/var/logs/madeup/lighttpd-access.log"

        proxy.server = ( "" =>
                           ( ( 
                               "host" => "123.456.789.012", # where you want to proxy to
                               "port" => 5678, # port you want to proxy to
                             ) ) 
                         )   
    }   
}

# Now go to http://made.up.hostname:1234 and you will get directed through to http://123.456.789.012:5678

VirtualBox commands

VBoxManage showvminfo [appliance name] |grep NIC

NIC 1 Rule(0):   name = AMQ admin page, protocol = tcp, host ip = 127.0.0.1, host port = 6666, guest ip = , guest port = 8161
NIC 1 Rule(1):   name = PRL, protocol = tcp, host ip = 127.0.0.1, host port = 5555, guest ip = , guest port = 5000
NIC 1 Rule(2):   name = SSH, protocol = tcp, host ip = 127.0.0.1, host port = 2222, guest ip = , guest port = 22
NIC 1 Rule(3):   name = XT, protocol = tcp, host ip = 127.0.0.1, host port = 8888, guest ip = , guest port = 8529
NIC 1 Rule(4):   name = web, protocol = tcp, host ip = 127.0.0.1, host port = 8080, guest ip = , guest port = 80