[Cafe] Cafe server information

[Alan Dawson]

Cafe Server progress

0.  Server Name decided...  sevenhills

1.  Debian Etch installed across mirrored disks
    ToDo .. install grub to both mirrored disk MBR to give choice of booting
from disk 1 or 2

2.  Xen Virtualisation Hypervisor added to sevenhills

3.  Xen Paravirtualised Debian Etch Server template built

4.  Paravirtualised monitoring server added and set to run constantly. 
Monitoring software used is munin.
    Machine name is "munin"
    As other virtual machines are added they should be set so that the
monitoring box can poll them.

    Resources used by "munin"  64MB RAM 2.5G HDD

5.  Second PV (paravirtual) server called "gareth".  Built from the Debian Etch
Template.      
    Resources used 1024MB Ram, 12G HDD ( see notes on altering disk size later
)

6.  Fully Virtualised server built.
    Resources Used 4G HDD, 1024MB Ram
    ... work in progress ...

static IP addresses for machines

sevenhills 192.168.1.200
munin	192.168.1.201
gareth 192.168.1.202


http://monitoring graphs available at 
http://192.168.1.201/munin/
    



getting a graphical console on one of the virtual servers
-----------------------------------------------------------

On a headless machine which we'd like to see use in a graphical way
Edit /etc/gdm/gdm.conf
add line under [XDMCP]
Enable=true

On your workstation start gmdXnestchooser

Select the remote machine and login


Resizing a disk
---------------

Server Gareth had initially a 2G HDD.  This isn't big enough to build a desktop
environment really.

gareth:/var/cache/apt/archives# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda1             2.0G  1.5G  414M  79% /
tmpfs                 513M     0  513M   0% /lib/init/rw
udev                   10M   24K   10M   1% /dev
tmpfs                 513M  4.0K  513M   1% /dev/shm


So.. on host sevenhills show the logical volumes...

sevenhills:~# lvs
  LV            VG          Attr   LSize   Origin Snap%  Move Log Copy%
  FullVirt      XenMachines -wi-a-  10.00G
  GarethRoot    XenMachines -wi-ao   2.00G
  GarethSwap    XenMachines -wi-ao 512.00M
  ISO           XenMachines -wi-ao   4.00G
  MuninRoot     XenMachines -wi-ao   2.00G
  MuninSwap     XenMachines -wi-ao 512.00M
  XenFileImages XenMachines -wi-ao   4.00G


we want to increase LV GarethRoot by 10G to 12G in size

sevenhills:~# lvextend -L +10G /dev/XenMachines/GarethRoot
  Extending logical volume GarethRoot to 12.00 GB

OK.. now we need to tell PV machine gareth that its got more capacity

so reboot it - so it picks up a bigger disk

gareth:/var/cache/apt/archives# init 6
gareth:/var/cache/apt/archives# Connection to 192.168.1.202 closed by remote
host.
Connection to 192.168.1.202 closed.

Log back in

aland at freedom:~$ ssh 192.168.1.202 -l root
root at 192.168.1.202's password:
Last login: Sun Dec  2 10:54:24 2007 from 192.168.1.26
Linux gareth 2.6.18-5-xen-686 #1 SMP Wed Oct 3 04:02:16 UTC 2007 i686

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
gareth:~#

online Resize the fs to the full available on the disk


gareth:~# resize2fs /dev/hda1
resize2fs 1.40-WIP (14-Nov-2006)
Filesystem at /dev/hda1 is mounted on /; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 1
Performing an on-line resize of /dev/hda1 to 3145728 (4k) blocks.
The filesystem on /dev/hda1 is now 3145728 blocks long.

  Logical volume GarethRoot successfully resized

gareth:~# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda1              12G  1.9G  9.4G  17% /
tmpfs                 513M     0  513M   0% /lib/init/rw
udev                   10M   24K   10M   1% /dev
tmpfs                 513M  4.0K  513M   1% /dev/shm

notice 12G disk now rather than 2G for /



As a suggestion for further investement if we have capacity ..  a pair of 500GB
sata disks ?




-- 
"The long revolution is creating small federated microsocieties, true guerilla
cells practising and fighting for this self-management. Effective radicality
authorises all variations and guarantees every freedom"