UUID is a nice way to generate (almost) unique id’s.
However on PostgreSQL 8.3 the data type exists, but if you wish to be able to generate UUID’s you need to get a module (in this case uuid-ossp).
On Debian this module is in the contrib package, so if you have not installed this before do it now
user@server:~$ sudo apt-get install postgresql-contrib
Then you need to “load” the module into PostgreSQL; or more accurately you tell PostgreSQL about the new functions this module has, how to reach them etc.
Depending on you security settings (in pg_hba.conf) you may need to log in as the postgres user on your system.
postgres@sever:~$ psql -d MYDB -U postgres -f /usr/share/postgresql/8.3/contrib/uuid-ossp.sql
apt-get is verifying the packages before installing them.
If the keys are not up to date, then apt-get upgrade will issue a warning.
WARNING: The following packages cannot be authenticated!
Install these packages without verification [y/N]?
The way to solve this is rather simple, just run apt-get update and it should download the keys automatically.
apt-key handles keys, using apt-key list will show you the keys that are on the computer.
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages have been kept back:
bind9-host dnsutils libbind9-50 libdns50 libisc50 libisccc50 libisccfg50 liblwres50 linux-generic linux-generic-pae linux-image-generic
0 upgraded, 0 newly installed, 0 to remove and 12 not upgraded.
The message has been kept back most often means that the upgrade was kept back due to dependencies that are not met.
Some possible solutions
- A simple way is to invoke dselect to help out with the update. dselect performs the actions necessary to realize that state (for instance, the removal of old and the installation of new packages).
- While apt-get and aptitude are basically the same, aptitude is sometimes better at handling dependencies than apt-get
- Another solution is to install the package using apt-get install to install the upgraded package and let apt-get install the missing dependencies
To re-configure exim4 on a Debian system just run
“$ dpkg-reconfigure exim4-config”
This will start the configuration process and you will be guided trough the configuration process.
By definition shorewall is not a firewall, it is a way to (more) easily configure iptables to work as a firewall.
- First install shorewall “$ apt-get intall shorewall”
- Enter /etc/shorewall
- Copy the example files from /usr/share/doc/shorewall-common/default-config/ (might also be located in /usr/share/doc/shorewall/default-config/) “$ cp /usr/share/doc/shorewall-common/default-config/* .”
- Edit the files and enter the data that your system has
- First create zones “$ nano zones”
#ZONE TYPE OPTIONS IN OPTIONS OUT OPTIONS
- Connect zones with interfaces”$ nano interfaces”
#ZONE INTERFACE BROADCAST OPTIONS
net eth0 detect tcpflags,blacklist,dhcp
vpn tun0 -
- Create policies “$ nano policy”
#SOURCE DEST POLICY LOG LEVEL LIMIT:BURST
fw net ACCEPT
vpn net ACCEPT
vpn fw ACCEPT
fw vpn ACCEPT
net all DROP info
all all DROP info
- Create rules “$ nano rules”
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/
# PORT(S) PORT(S) DEST LIMIT GROUP
ACCEPT net fw tcp 22 # ssh
ACCEPT net fw tcp 80 # web
- Verify that the rules are fine “$ shorewall check”
- Edit /etc/default/shorewall and set startup to 1
# prevent startup with default configuration
# set the following varible to 1 in order to allow Shorewall to start
- Start the firewall “$ /etc/init.d/shorewall start”
If you later decide to update rules, zones etc run “$ /etc/init.d/shorewall restart” to load the changes.
To just get the version number
Turns out using Debian it is very simple to get memtest86+ to appear in the grub boot up menu.
Simply install it as usual using apt-get.
After the installation is complete do a grub-install.
That’s it, after rebooting memtest86+ is now in the grub menu.
(Now how come it was not possible to google out this info;) )