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Mar
30
2015
How to create an archlinux docker image from the latest bootstrap

Docker is a wonderful application for creating development images quick and not-so-dirty.

I am working -mostly- on archlinux so here are the steps:


[~]> wget -c ftp://ftp.otenet.gr/pub/linux/archlinux/iso/latest/archlinux-bootstrap-2015.03.01-x86_64.tar.gz
[~]> tar xf archlinux-bootstrap-2015.03.01-x86_64.tar.gz
[~]> cd root.x86_64
[~]> tar cf archlinux-bootstrap-2015.03.01-x86_64.tar .
[~]> docker import - archlinux:bootstrap < archlinux-bootstrap-2015.03.01-x86_64.tar

after that you should update the docker image:


$ docker run -t -i --rm archlinux:bootstrap bash
# echo 'Server = http://ftp.otenet.gr/linux/archlinux/$repo/os/$arch' > /etc/pacman.d/mirrorlist
# pacman-key --init
# pacman-key --populate archlinux
# pacman -Syuvw
# pacman -Suv

to save your changes, open a new terminal and:


[~]> docker commit -p -m "archlinux bootstrap latest" -a USERNAME DOCKER_ID archlinux:bootstrap

replace your username and your docker_id accordingly.

You can now exit from your docker image.

To help you even more, check out this video i’ve made:

archlinux docker bootstrap image from Evaggelos Balaskas on Vimeo.

Tag(s): archlinux, docker
Mar
30
2015
btrfs scrub example

# /sbin/btrfs fi show /mnt/VB0250EAVER/

Label: ‘VB0250EAVER’ uuid: e76cefe1-7ce3-43fa-953a-31602616d9ca
Total devices 2 FS bytes used 106.34GiB
devid 1 size 232.88GiB used 109.03GiB path /dev/mapper/sdd
devid 2 size 232.88GiB used 109.01GiB path /dev/mapper/sde

Btrfs v3.18


# /sbin/btrfs scrub start -Bd /mnt/VB0250EAVER/

scrub device /dev/dm-3 (id 1) done
scrub started at Mon Mar 30 16:48:32 2015 and finished after 1150 seconds
total bytes scrubbed: 106.34GiB with 0 errors
scrub device /dev/mapper/sde (id 2) done
scrub started at Mon Mar 30 16:48:32 2015 and finished after 1133 seconds
total bytes scrubbed: 106.34GiB with 0 errors


# btrfs filesystem df /mnt/VB0250EAVER/

Data, RAID1: total=106.00GiB, used=104.84GiB
Data, single: total=8.00MiB, used=0.00B
System, RAID1: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00B
Metadata, RAID1: total=3.00GiB, used=1.50GiB
Metadata, single: total=8.00MiB, used=0.00B
GlobalReserve, single: total=512.00MiB, used=0.00B

Tag(s): btrfs
Mar
30
2015
btrfs subvolumes and Snapshots

Just a mini old page about btrfs: subvolumes and snapshots

Tag(s): btrfs
Mar
24
2015
trying ipv6 only web

Although it feels really lonely … not a lot content yet.

All you need is an ISP that gives you an IPv6 address space, pppd and some free time !

You need to find out that your CPE can work like a modem so that PPPoE can pass through.

Point-to-Point Protocol Daemon

/etc/ppp/peers/ipv6

+ipv6 ipv6cp-use-ipaddr
noip
-chap
defaultroute
usepeerdns
mtu 1492
# debugging
debug
dump
# authentication
name “USERNAME@DOMAIN.gr”
hide-password
noauth
# device
plugin rp-pppoe.so
eth0

The noip means no IPv4 ip
+ipv6 means IPv6

” If the ipv6cp-use-ipaddr option is given, the local identifier is the local IPv4 address “

You should replace the USERNAME & DOMAIN according your credentials.

you need to edit /etc/ppp/pap-secrets to add your password for your account:

USERNAME@DOMAIN.gr * PASSWORD

ip6tables

/etc/iptables/ip6tables.rules



*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p ipv6-icmp -j ACCEPT
COMMIT

Be aware that IPv6 will give/configure your network device, through ICMPv6 router advertisements, so you MUST fix your firewall

IPv6 DNS

If your ISP doesnt provide you with IPv6 DNS servers, edit your /etc/resolv.conf to add opendns servers:

2620:0:ccc::2

2620:0:ccd::2

Connect


# pon ipv6

Plugin rp-pppoe.so loaded.
RP-PPPoE plugin version 3.8p compiled against pppd 2.4.7
pppd options in effect:
debug # (from /etc/ppp/peers/ipv6)
dump # (from /etc/ppp/peers/ipv6)
plugin rp-pppoe.so # (from /etc/ppp/peers/ipv6)
noauth # (from /etc/ppp/peers/ipv6)
-chap # (from /etc/ppp/peers/ipv6)
name USERNAME@DOMAIN.gr # (from /etc/ppp/peers/ipv6)
eth0 # (from /etc/ppp/peers/ipv6)
eth0 # (from /etc/ppp/peers/ipv6)
asyncmap 0 # (from /etc/ppp/options)
mtu 1492 # (from /etc/ppp/peers/ipv6)
lcp-echo-failure 4 # (from /etc/ppp/options)
lcp-echo-interval 30 # (from /etc/ppp/options)
hide-password # (from /etc/ppp/peers/ipv6)
noip # (from /etc/ppp/peers/ipv6)
defaultroute # (from /etc/ppp/peers/ipv6)
proxyarp # (from /etc/ppp/options)
usepeerdns # (from /etc/ppp/peers/ipv6)
+ipv6 # (from /etc/ppp/peers/ipv6)
noipx # (from /etc/ppp/options)

Networking



# clear ; ip -6 a && ip -6 r

the result:

1: lo: mtu 65536
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
3: ppp0: mtu 1492 qlen 3
inet6 2a02:580:31a:0:744e:f2f1:bc63:dbdd/64 scope global mngtmpaddr dynamic
valid_lft 3465sec preferred_lft 2865sec
inet6 fe80::744e:f2f1:bc63:dbdd/10 scope link
valid_lft forever preferred_lft forever

2a02:580:31a::/64 dev ppp0 proto kernel metric 256 expires 3464sec
fe80::/10 dev ppp0 metric 1
fe80::/10 dev ppp0 proto kernel metric 256
default via fe80::90:1a00:1a0:80be dev ppp0 proto ra metric 1024 expires 1664sec

Verify

http://ipv6-test.com/ipv6-test

ipv6_only.png

Tag(s): ipv6
Mar
20
2015
One step closer to IPv6

It was time for me to start using the #IPv6.

My VPS hosting provider: edis have already allocated me a

2a01:7a0:10:158:255:214:14:0/112

and some extra info

Gateway:
     2a01:7a0:10::1
Nameserver:
     2a03:f80:ed15:ed15:ed15:ed15:d8b9:da76
     2a03:f80:ed15:ca7:ea75:b12d:7b0:3e5b

I have two network cards (I run my own AUTH-NS server and some greek registrars require two different IPs for that).

I have split up the above /112 to two /113 subnets.

2a01:7a0:10:158:255:214:14::/113
2a01:7a0:10:158:255:214:14:8000/113

My settings are based on CentOS 6.6 as the time of this article.

 

Part Zero: kernel

 

First thing first, tell kernel to support ipv6 by editing: /etc/sysctl.conf

comment (if there is) the below line:

# net.ipv6.conf.all.disable_ipv6=1

This mean that next time you reboot your machine, ipv6 will be enabled.
There is another way, if you dont want to reboot your vps, by running as root:


sysctl net.ipv6.conf.all.disable_ipv6=0 

 

Part One: Network

 

Edit your ifcfg-eth* files:

/etc/sysconfig/network-scripts/ifcfg-eth0

IPV6INIT=yes
IPV6ADDR=2a01:7a0:10:158:255:214:14::/123
IPV6ADDR_SECONDARIES=”2a01:7a0:10:158:255:214:14:80/123”
IPV6_DEFAULTGW=2a01:7a0:10::1

/etc/sysconfig/network-scripts/ifcfg-eth1

IPV6INIT=yes
IPV6ADDR=2a01:7a0:10:158:255:214:14:8000/113
IPV6_DEFAULTGW=2a01:7a0:10::1

PLZ dont get confused about eth0. I will circle back to this.

Restart your network:


/etc/init.d/network restart 

and verify your network settings:


 ip -6 a
 ip -6 r

 

Part Two: Firewall

 

My default policy is DROP everything and open only the ports you are running services.
Same rule applies for IPv6 too.

:INPUT DROP [0:0]
-A INPUT -i lo -j ACCEPT
-A INPUT -m state –state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p ipv6-icmp -j ACCEPT
-A INPUT -j REJECT –reject-with icmp6-adm-prohibited
:FORWARD DROP [0:0]
-A FORWARD -j REJECT –reject-with icmp6-adm-prohibited
:OUTPUT ACCEPT [0:0]

At this moment, i only accept PING6 to my VPS server.
Testing this from another machine (with ipv6 support):


 ping6 -c3 2a01:7a0:10:158:255:214:14::

and the result is something like this:

PING 2a01:7a0:10:158:255:214:14::(2a01:7a0:10:158:255:214:14:0) 56 data bytes
64 bytes from 2a01:7a0:10:158:255:214:14:0: icmp_seq=1 ttl=60 time=72.5 ms
64 bytes from 2a01:7a0:10:158:255:214:14:0: icmp_seq=2 ttl=60 time=66.9 ms
64 bytes from 2a01:7a0:10:158:255:214:14:0: icmp_seq=3 ttl=60 time=66.3 ms

— 2a01:7a0:10:158:255:214:14:: ping statistics —
3 packets transmitted, 3 received, 0% packet loss, time 2067ms
rtt min/avg/max/mdev = 66.355/68.618/72.573/2.822 ms

At this point we are very happy with our selfs (ipv6 related)!

 

Part Three: Web Server

 

What’s the point of having an ipv6 server and not apply some services on ?
Lets start with the apache web server.

I’ve split up my eth0 to /123 subnets cause i want to use different IPs for every service i have.
Thats way my eth0 is like that.

I chose the 2a01:7a0:10:158:255:214:14:80 as my ipv6 ip for my site.

Our web server needs to listen to ipv6.

This is tricky cause apache on ipv6 is using : as a delimiter.
So my http changes are something like these:

Listen 158.255.214.14:80
Listen [2a01:7a0:10:158:255:214:14:80]:80

to support virtual hosts:

NameVirtualHost 158.255.214.14:80
NameVirtualHost [2a01:7a0:10:158:255:214:14:80]:80

To dual stack my site:

‹ VirtualHost 158.255.214.14:80 [2a01:7a0:10:158:255:214:14:80]:80 ›

restart your apache:


/etc/init.d/httpd restart

Dont forget to manipulate your firewall settings:

-A INPUT -m state –state NEW -m tcp -p tcp -d 2a01:7a0:10:158:255:214:14:80/123 –dport 80 -j ACCEPT

restart your firewall:


/etc/init.d/ip6tables restart

 

Part Four: DNS

 

The only thing that is left for us to do, is to add a AAAA resource record in our dns zone:

in my bind-file format zone: balaskas.gr

@ IN AAAA 2a01:7a0:10:158:255:214:14:80

you have to increment the SERIAL number in your zone and then reload your zone.
I use PowerDNS so it’s:


# pdns_control reload balaskas.gr
Ok

 

Part Five: Validate

 

To validate your dual stack web site, you use go through:

ipv6-test

 

 

UPDATE: 2015 03 23

 

 

Part Six: Mail Server

Imap Server

I use dovecot for imap server. To enable IPv6 in dovecot is really easy. You just uncomment or edit Listen parameter:

listen = *, ::

restart dovecot service and check the dovecot conf:


# doveconf | grep ^listen
listen = *, ::

I use STARTTLS, so my firewall settings should be like these:

-A INPUT -m state –state NEW -m tcp -p tcp -d 2a01:7a0:10:158:255:214:14::/112 –dport 143 -j ACCEPT

Just dont forget to restart and verify your ip6table !

SMTP Server

It’s really easy for postfix (my SMTP server) too. You just have to remember that you need to use brackets for [b]IPv6[/url].

## mynetworks = 127.0.0.0/8 158.255.214.14/31
mynetworks = 127.0.0.0/8 158.255.214.14/31 [2a01:7a0:10:158:255:214:14::]/112

## inet_protocols = ipv4
inet_protocols = all

restart your smtp service and you are OK.

Firewall settings: /etc/sysconfig/ip6tables

-A INPUT -m state –state NEW -m tcp -p tcp -d 2a01:7a0:10:158:255:214:14::/112 –dport 25 -j ACCEPT
-A INPUT -m state –state NEW -m tcp -p tcp -d 2a01:7a0:10:158:255:214:14::/112 –dport 587 -j ACCEPT

Tag(s): ipv6
Mar
13
2015
web bank security

Disclaimer: updated 20150413

Seems that this post has gained some publicity over the web.
I need to disclaim some things, such as:
- I am no a security expert guy. Some of the below security tech info may be wrong!
- I dont claim that i have found a security hole.
- I am not telling you that the entire web banking in greece is not secure.
- I published this story to raise awareness.

Even if all of my comments were wrong I wouldnt expect someone telling me to remove it.
More clever people than me, could have commented on my screenshot and put me in place.

Again, thanks for your support.

End of Disclaimer

Update 20150315

After reading a lot of comments and discussing this story with a lot of good friends of mine, i came to the decision to remove this blog post. I have my personal reasons on the subject and no one had affect my decision. I have had a lot of stress on the matter and i would like to put this behind me.

Thank you again, for all your support.

Mar
02
2015
xfce 4.12

so a few days ago xfce released 4.12 !!!

I keep my own custom local repository and just found the time to update my xfce to the latest version !

my PKGBUILDs are mostly a template of the below file (git repo)


# Contributor: Evaggelos Balaskas < Evaggelos _AT_ Balaskas _DOT_ GR >
# Maintainer:  Evaggelos Balaskas < Evaggelos _AT_ Balaskas _DOT_ GR >

_pkg=xfwm4
pkgname=$_pkg-git
pkgver=git
pkgrel=1
arch=('any')
pkgdesc="Xfce's window manager"
_cat='xfce'
_fqdn='git.xfce.org'
url="http://$_fqdn/$_cat/$_pkg"
license=('GPL v2')

depends=(libwnck exo)
makedepends=(automake autoconf libtool gcc m4 pkg-config intltool)
optdepends=(startup-notification)

conflicts=($_pkg)
provides=($_pkg)
replaces=($_pkg)

_gitroot="git://$_fqdn/$_cat"
_gitname=$_pkg

pkgver() {
    date +%Y%m%d
}

build() {

    if [ -d $_gitname ] ; then
        msg "cd $_gitname && git pull origin"
        cd $_gitname && git pull origin
        msg "The local files are updated."
    else
        msg "git clone $_gitroot/$_gitname"
        git clone $_gitroot/$_gitname
        msg "The local files are updated."
    fi

    cd $srcdir/$_pkg
    ./autogen.sh --prefix=/usr --disable-debug 

    make

}

package() {
    cd $srcdir/$_pkg
    make DESTDIR=$pkgdir install
}

The result is something like this:

xfce_412.png

If you want to check my entire xfce custom repo, just click xfce-core_4.12.zip

UPDATE

I used this order of installation:



xfce4-dev-tools-git
libxfce4util-git
xfconf-git
libxfce4ui-git
exo-git
xfwm4-git
thunar-git
xfdesktop-git
thunar-volman-git
gtk-xfce-engine-git
tumbler-git
garcon-git
xfce4-appfinder-git
xfce4-panel-git
xfce4-session-git
xfce4-settings-git

Tag(s): xfce, archlinux