LinuxMCE - User contributions [en]

Create RAID in LMCE

2012-03-13T22:39:33Z

Dirk: Versioninfo update

{{Versioninfo|1004Status=Works with hotfix|1004UpdatedDate=13th Mar 2012|1004UpdatedBy=[[User:Dirk|Dirk]]|}}
{| align="right"
| __TOC__
|}
[[Category: Tutorials]]
[[Category: Storage]]
[[Category: Admin Website]]
== Introduction ==
RAID (Redundant Array of Independent Drives) refers to a data storage scheme which has as a benefit increase of the data integrity, fault-tolerance, throughput and/or capacity
There are 3 standard RAID levels which can be used in LMCE, to define RAIDS:
=== RAID 0 ===
* Striped Set (2 disk minimum) without parity
* provides improved performance
* additional storage
* no fault tolerance from disk errors or disk failure. Any disk failure destroys the array, which becomes more likely with more disks in the array
=== RAID 1 ===
* Mirrored Set (2 disks minimum) without parity.
* Provides fault tolerance from disk errors and single disk failure.
* Increased read performance occurs when using a multi-threaded operating system that supports split seeks, very small performance reduction when writing.
* A drive has its data duplicated on another different drive. If either drive fails, the other continues to function as a single drive until the failed drive is replaced.
Conceptually simple, RAID 1 is popular for those who require fault tolerance and don't need top-notch read performance.
=== RAID 5 ===
* Striped Set (3 disk minimum) with Distributed Parity
* Distributed parity requires all but one drive to be present to operate
* drive failure requires replacement, but the array is not destroyed by a single drive failure.
* Upon drive failure, any subsequent reads can be calculated from the distributed parity such that the drive failure is masked from the end user.
* The array will have data loss in the event of a second drive failure and is vulnerable until the data that was on the failed drive is rebuilt onto a replacement drive
== Creating RAID ==
[[Image:AdvancedRaid.jpeg]]
# Go to '''[[LinuxMCE Admin Website]]-->Advanced->Configuration->[[RAID]]'''
## Specify the computer that should hold the RAID in the Parent section.
## Give a Description to the Raid you’re creating.
## Choose the type of RAID, according to what you need to do.
## Check the Use automatically box, if you want your data to be stored automatically using this RAID.
## Choose what kind of data structure you want for this RAID. Then click on the Add button to save your settings.
# Choose the disk drives you want to include in the RAID, by selecting the available ones from the drive list. The list contains only the disks that there are not used. Also you have the option to add spare disks.
# When you have finished adding your disks, press the ‘Create RAID array’ button, to re-write your data in the desired pattern. You will see your RAID created in the list and you will be able to access the advanced configuration page, to add new drives, or to delete it.
# In 10.04, at the moment, a manual fix before reboot seems necessary: sudo mdadm --detail --scan >> /etc/mdadm/mdadm.conf

Note: This is a totally software RAID, you don’t need to activate the RAID in your BIOS.

== Troubleshooting ==
#If the array keeps coming back as failed, try stopping non-existant RAID devices:
## sudo mdadm --stop /dev/md0
## sudo mdadm --stop /dev/md1
#If you continue having problems then try ssh'ing in, delete any partitions using fdisk, reboot and try again.

Create RAID in LMCE

2012-03-13T22:33:42Z

Dirk: temporary hotfix for 10.04

{{Versioninfo}}
{| align="right"
| __TOC__
|}
[[Category: Tutorials]]
[[Category: Storage]]
[[Category: Admin Website]]
== Introduction ==
RAID (Redundant Array of Independent Drives) refers to a data storage scheme which has as a benefit increase of the data integrity, fault-tolerance, throughput and/or capacity
There are 3 standard RAID levels which can be used in LMCE, to define RAIDS:
=== RAID 0 ===
* Striped Set (2 disk minimum) without parity
* provides improved performance
* additional storage
* no fault tolerance from disk errors or disk failure. Any disk failure destroys the array, which becomes more likely with more disks in the array
=== RAID 1 ===
* Mirrored Set (2 disks minimum) without parity.
* Provides fault tolerance from disk errors and single disk failure.
* Increased read performance occurs when using a multi-threaded operating system that supports split seeks, very small performance reduction when writing.
* A drive has its data duplicated on another different drive. If either drive fails, the other continues to function as a single drive until the failed drive is replaced.
Conceptually simple, RAID 1 is popular for those who require fault tolerance and don't need top-notch read performance.
=== RAID 5 ===
* Striped Set (3 disk minimum) with Distributed Parity
* Distributed parity requires all but one drive to be present to operate
* drive failure requires replacement, but the array is not destroyed by a single drive failure.
* Upon drive failure, any subsequent reads can be calculated from the distributed parity such that the drive failure is masked from the end user.
* The array will have data loss in the event of a second drive failure and is vulnerable until the data that was on the failed drive is rebuilt onto a replacement drive
== Creating RAID ==
[[Image:AdvancedRaid.jpeg]]
# Go to '''[[LinuxMCE Admin Website]]-->Advanced->Configuration->[[RAID]]'''
## Specify the computer that should hold the RAID in the Parent section.
## Give a Description to the Raid you’re creating.
## Choose the type of RAID, according to what you need to do.
## Check the Use automatically box, if you want your data to be stored automatically using this RAID.
## Choose what kind of data structure you want for this RAID. Then click on the Add button to save your settings.
# Choose the disk drives you want to include in the RAID, by selecting the available ones from the drive list. The list contains only the disks that there are not used. Also you have the option to add spare disks.
# When you have finished adding your disks, press the ‘Create RAID array’ button, to re-write your data in the desired pattern. You will see your RAID created in the list and you will be able to access the advanced configuration page, to add new drives, or to delete it.
# In 10.04, at the moment, a manual fix before reboot seems necessary: sudo mdadm --detail --scan >> /etc/mdadm/mdadm.conf

Note: This is a totally software RAID, you don’t need to activate the RAID in your BIOS.

== Troubleshooting ==
#If the array keeps coming back as failed, try stopping non-existant RAID devices:
## sudo mdadm --stop /dev/md0
## sudo mdadm --stop /dev/md1
#If you continue having problems then try ssh'ing in, delete any partitions using fdisk, reboot and try again.

Access Point

2011-10-24T13:38:27Z

Dirk: /* Restart Networking */

{{versioninfo|810Status=relevant|810UpdatedDate=20th Sept 2010|810UpdatedBy=[[User:phenigma|phenigma]]}}
[[Category: Tutorials]]
{| align="right"
| __TOC__
|}
= Introduction =

This tutorial describes how to add Access Point functionality to your LinuxMCE Core/Hybrid. The Core/Hybrid will then act as a WiFi access point permitting wireless devices to connect to the core, the internal network and the Internet. The drivers you choose will depend on your specific hardware. Setting up an Access Point on your core allows you to use wireless orbiters such as the [[WebDT 366]] or [[Nokia N800]]/N900 without installing a separate wireless access point on your network.

= Using nl80211 drivers (from back-ports) =

== Hardware ==
A lot of modern hardware works. Look up your device at http://wireless.kernel.org/en/users/Devices to determine which driver your card uses. The driver needs to support AP, you can check that the driver has this support at http://wireless.kernel.org/en/users/Drivers/. If the driver does not have AP support then you will not be able to operate the card as an Access Point.

Two Wireless-N adaptors that are known to work:
* Atheros Communications Inc. AR928X Wireless Network Adaptor (PCI-Express) (rev 01)
** This was pre-installed on a Zotac IONITX-A-U Atom N330 1.6 Ghz
** Uses the ath9k driver
* Atheros AR9280 MAC/BB Rev:2 AR5133 RF Rev:d0
** This is a D-Link DWA-522 Extreme N PCI Adaptor
** Uses the ath9k driver
* LinuxMCE 0810 BETA - Snapshot DVD 25289

== Overview ==
* -> eth0 connects to internal network LMCE
* -> eth1 connects to the internet
* -> wlan0 is the wireless card

== Required packages ==
=== Add the intrepid-backports repository ===
Adding the intrepid-backports repo gives us access to newer wireless drivers.
$ echo 'deb http://archive.ubuntu.com/ubuntu intrepid-backports main universe' | sudo tee -a /etc/apt/sources.list
$ sudo apt-get update

=== Install required packages ===
Install compat-wireless drivers including the mac80211/cfg80211 modules and the network bridge utilities.
$ sudo apt-get install linux-backports-modules-intrepid bridge-utils

=== Download, build and install hostapd ===
The hostapd package that ships with intrepid (0.5.10) is outdated, newer functionality is required. Grab the most recent version that works with the compat-wireless drivers that we installed. 0.6.10 is the newest in the 0.6.x tree but it has a bug that causes it to fail with some cards, use 0.6.9.

Install build dependencies for hostapd
$ sudo apt-get install libnl-dev libssl-dev
Get hostapd 0.6.9
$ wget http://w1.fi/releases/hostapd-0.6.9.tar.gz
$ tar xvf hostapd-0.6.9.tar.gz
$ cd hostapd-0.6.9/hostapd
$ cp defconfig ./.config
Edit the .config file to enable the proper drivers:
*Enable nl80211 driver
CONFIG_DRIVER_NL80211=y
*Enable IEEE 802.11n (High Throughput) support
CONFIG_IEEE80211N=y
Build and Install hostapd
$ make
$ sudo make install
Copy the config file to /etc/hostapd
$ sudo mkdir -p /etc/hostapd
$ sudo cp hostapd.conf /etc/hostapd

== Config Files ==
=== /etc/network/interfaces ===
Make a backup of your original interfaces file:
$ sudo mv /etc/network/interfaces /etc/network/interfaces.bak
The interfaces file shown here is based on the setup described in the overview above.
auto lo eth1 br0 eth0
# Loopback Interface
iface lo inet loopback
# Internet Interface
iface eth1 inet dhcp
# LAN Interface
iface eth0 inet manual
up /sbin/ifconfig eth0 up
down /sbin/ifconfig eth0 down
# Wireless Interface
iface wlan0 inet manual
# Wireless/LAN Bridge
iface br0 inet static
address 192.168.80.1
network 192.168.80.0
netmask 255.255.255.0
broadcast 192.168.80.255
pre-up /usr/sbin/brctl addbr br0
pre-up /usr/sbin/brctl addif br0 eth0
pre-up /usr/local/bin/hostapd -B /etc/hostapd/hostapd.conf
pre-up /usr/sbin/brctl addif br0 wlan0
up /sbin/ifconfig br0 inet 192.168.80.1 broadcast 192.168.80.255 netmask 255.255.255.0
post-down /usr/sbin/brctl delif br0 eth0
post-down /usr/sbin/brctl delif br0 wlan0
post-down /usr/sbin/brctl delbr br0

=== /etc/hostapd/hostapd.conf ===
Edit /etc/hostapd/hostapd.conf and verify/change the following:
interface=wlan0
driver=nl80211
ssid=yourssidhere
hw_mode=g
ieee80211n=1

=== /etc/default/dhcp3-server ===
Configure the dhcp server to respond to request from devices on the bridge instead of the wired connection alone.
$ echo 'INTERFACES="br0"' | sudo tee /etc/default/dhcp3-server

== Security/Encryption ==
All security/encryption related settings are in /etc/hostapd/hostapd.conf. Edit this file as needed.
A good starting point for a wpa & wpa2 enabled access point is:

macaddr_acl=0
auth_algs=1
ignore_broadcast_ssid=0
wpa=3
wpa_passphrase=YourPassPhrase
wpa_key_mgmt=WPA-PSK
wpa_pairwise=TKIP
rsn_pairwise=CCMP

(from: http://linuxwireless.org/en/users/Documentation/hostapd#Authentication_and_Encryption )

== Restart Networking ==
Restart the networking engine, or reboot.
$ sudo service networking restart
'''or''' (in case the above didn't work)
$ /etc/init.d/networking restart

= Using madwifi drivers =
WORK IN PROGRESS

== Hardware setup ==

* Dell Optiplex Gx620
* WiFi card with Atheros chipset (using madwifi drivers)
* Linux MCE 810 alpha2

If you install LMCE from scratch make sure that your wifi card is NOT inserted prior to installation so that LMCE doesn't use it as the internal network interface. After LCME installation has finished, insert the wifi card.

== Overview ==

the idea is to combine or bridge eth1 and ath0 to a new virtual interface called br0.

* -> eth0 connects to my ADSL modem (192.168.1.0)
* -> eth1 connects to my internal LAN switch (192.168.80.0)
* -> ath0 connects the wireless part of my internal network (192.168.80.0)

== Needed packages ==

* hostapd
* bridge

== Config files ==

=== /etc/network/interfaces ===

We'll make a copy of /etc/network/interfaces in case something goes wrong before we edit it.

mv /etc/network/interfaces /etc/network/interfaces.bck

joe /etc/network/interfaces

auto lo eth0 eth1 br0
automatically initialise eth0 (external interface) eth1 (internal LAN) and br0 (our bridge interface). Keep ath0 out of this for now, we'll initialise it separately.

iface lo inet loopback

# Internet Interface
iface eth0 inet static
address 192.168.1.2
netmask 255.255.255.0
gateway 192.168.1.1
dns-nameservers 192.168.1.1

Fill in your own settings here, in my case 192.168.1.1 is the ADSL modem. Alternatively you can use dhcp to get the adress details from your ADSL modem.

# LAN interface
iface eth1 inet manual
up /sbin/ifconfig eth0 up
down /sbin/ifconfig eth0 down

The internal interface, note that it doesn't get an adress assigned.

# Wireless interface
auto ath0
iface ath0 inet manual
up /sbin/ifconfig ath0 up

The wireless interface, again no adress details here.

iface br0 inet static
address 192.168.80.1
network 192.168.80.0
netmask 255.255.255.0
broadcast 192.168.80.255
pre-up /usr/sbin/brctl addbr br0
pre-up /usr/sbin/brctl addif br0 eth1

The fun part. Finally we assign the adress for the internal LAN to the bridge interace br0 (I'm sticking here with the standard LMCE network 80.0). The pre-up will create a bridge and add the eth1 interface to it.

pre-up /sbin/wlanconfig ath0 destroy
pre-up /sbin/wlanconfig ath0 create wlandev wifi0 wlanmode ap
pre-up /sbin/iwconfig ath0 channel 3

This part is necessary as the atheros interface has some issues to switch ino access point mode (master mode)

pre-up /usr/sbin/brctl addif br0 ath0

After firing up the wireless interface we add it to the bridge as well.

post-down /usr/sbin/brctl delif br0 eth1
post-down /usr/sbin/brctl delif br0 ath0
post-down /usr/sbin/brctl delbr br0

Just some lines to define how to cleanly shut down the bridge: remove both interfaces and then remove the bridge interace itself

We need to set the bridge (which contains eth1 and ath0) as the new interface for the dhcpd server.
Edit /etc/default/dhcp.conf as followed:

INTERFACES="br0"

/etc/default/dhcpd3/dhcpd.conf

=== wireless configuration ===

We'll use hostapd to manage the wireless part as it provides WPA encryption. I suggest that you first try to setup your network without encryption, make sure it works and then enable encryption.

== Enable WPA encryption ==

* edit the /etc/hostapd

== Set static IP adresses ==

It is possible to set static ip adresses manually instead of using LMCE.