May 3, 2019

disable su on debian

is your VM safe enough? A VM is only safe when it’s powered OFF Why? You have prepared your VM with CDD and you want to be sure that changes will be saved on the original ISO so editing a live machine, will not be possible. You are forced to firstly update your versioned CDD/ISO so who will come after you, will be able to exactly understand what and why you did.

April 18, 2017

GNU awk is required for lib/memtype.h made by memtypes.awk. BSD awk complains: awk: gensub doesn't support backreferences (subst "\1")

This error is given when you try to compile quagga. The easy solution is to tested with Debian 8 and Quagga 1.2.1 apt-get install -y gawk Compile quagga If you need more help, here’s the list of the needed dependencies to compile correctly. apt-get install -y build-essential gawk libreadline-dev pkg-config libc-ares-dev After this, a simple ./configure [options] make && make install will do the rest.

April 15, 2017

keepalived, virtual IP plus alerting

KeepAliveD is a tool you should learn as soon as possible. You are going to need this wonderful instrument and its magnificent powers. All starts with a a simple apt-get install keepalived and continues with a very short configuration needed. requirements Create two Debian 8 VM on the same network. debianA: 192.168.60.101/24 debianB: 192.168.60.102/24 Your firewall must allow VRRP protocol communication between clients on the same subnet.

April 15, 2017

DD, monitor current status and speed

One of the most useful command in Linux, is dd. We also know that dd provides info regarding the current status, using kill: kill -USR1 <pidof dd> but I really prefer the pv way (apt-get install pv) # We usually do this way dd if=my.iso of=/dev/sdb # This is the "pv" way dd if=my.iso | pv | dd of=/dev/sdb Of course, you need apt-get install -y pv before, but piping through pv, allow you to see the status, in real time.

April 15, 2017

openvpn, tap vs tun, differences

While creating an OpenVPN server you should think what you are going to use it for. Long story short Use tap for a layer 2 vpn, tun for a layer 3. tap Tap is a virtual eth interface and, you will be able to put the interface tap0 into a bridge: apt-get install bridge-utils brctl addbr br0 brctl addif br0 tap0 eth0 tun Tun is for a direct IP connection between two points.

April 15, 2017

debian preseed, prompt user input

Debian preseed As I told in a previous article, preseeding is very useful, you can do many stuff without the need of an external system like Puppet o Chef. A problem I encountered while preseeding our farm, was to ask user just some input or to confirm it. The solution is very simple but not well documented and after a bit of research, I found the way. # preseeding the value, this will not be asked.

March 18, 2017

Advanced provisioning with simple-cdd and git

Installing machines, is now more easy, as seen in my previous article. What happens if we want to update a configuration? If we only rely to the simple-cdd way, we are going to rebuild the iso and reinstall our VMs, which is not we always want to do. In my case, I have found many tools able to achieve this goal. Chef, PuppetLabs are just two of those. Do you really want to use something you need to learn?

March 18, 2017

dhcpd, name your machines

As seen in my previous blog post, provisioning machines is quite simple, but the hostname must be unique, so we want an automatic way to configure it. installation of a dhcpd This is not what I want to share, you will find here the how-to. dhcpd.conf option domain-name-servers 8.8.8.8, 8.8.4.4; option domain-name "brugnara.me"; default-lease-time 600; max-lease-time 7200; # Show that we want to be the only DHCP server in this network: authoritative; subnet 192.

March 18, 2017

Proxmox net card association with udev

udev eth association with Proxmox If you are here, you may have the same problem as I encountered. The way you create net card in Proxmox, is not predictable in linux. If you have seen my article about simple-cdd, you may better understand why we solved this way. udev works with address Yes. It is. But it works with regular expressions, so we can use for our goal. How? Check this base.

March 18, 2017

simple-cdd. A way to provision you machines effortless

What is simple-cdd As you can read here, simple-cdd simply is a limited, though relatively easy to use tool to create a customized DebianInstaller CD. It is a wrapper around debian-cd and mirroring tools used to create a customized DebianInstaller CD image. It takes a list of packages to install, and debconf pre-seeding files to pre-configure the installation. It has some support for multiple profiles and custom post-install scripts for things that can’t be configured by debconf preseeding.