Maintenance reference

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Revision as of 18:42, 23 June 2013 by M (talk | contribs)

Reference

LAN IP addresses
We want all IP address management to happen on the Buffalo DD-WRT router, as much as possible.

Ideally, static IPs will be served up to every known box based on MAC address. Then no matter what OS is booted, the machine will have the same name and IP address. The router is slick, it can do it, but be careful to Save AND Apply changes there.

airstation   192.168.21.200
dune         192.168.21.179

dhcp range for unknown devices: 2-99

(still more to do to make this consistent, keep at it)
Adding a user to the server
su -
# only needed if you want them to have their own group (otherwise use "users" group)
groupadd #newuser#
# the additional groups here are optional
useradd #newuser# -m -g #newuser# -G users,wheel,audio,video,games,dvd,usb -s /bin/bash
passwd #newuser#
mkdir /home/#newuser#
chown #newuser#:users /home/#newuser#

# grant ssh access by adding to "AllowUsers"
em /etc/ssh/sshd_config
/etc/init.d/sshd restart

# grant samba access to home folder
# it's already set up in /etc/samba/smb.conf
# but the user must be manually added to samba
# use same pwd as before to sync them
smbpasswd -a #newuser#
/etc/init.d/samba restart

# YOU PROBABLY HAVE TO RESTART ANY STUPID WINDOWS BOX before it will see things correctly!  crazy
# you can try this in Windows but it didn't work for me:  
#  net use
#  net session \\samba.server.ip.address /delete
Updating mediawiki installation
cd /var/www/localhost/htdocs/mediawiki
emacs LocalSettings_redirector.php (to hardcode each site)
php maintenance/update.php
(repeat for each site)
emacs LocalSettings_redirector.php (to reset dynamic behavior)
Creating a new ssh key pair for no-password access to a remote system
wow I just had serious issues with basic ssh usage, so i'll put a summary on the wiki
   basically most misunderstandings stem from describing these two:
       client: machine that is trying to ssh into the server
       server: machine that the client user wants to get to
   most poor sots are just sitting on the client
   and they create a pair and push their public key to the server
   but in my case, more often, i want to create a pair on the server
   and push the private key to the multiple places i need to connect FROM
   when doing that, you have to push the public key into the server's authorized_keys
   and configure the client to juggle multiple private keys

       create a key pair:
           ssh suser@server
           ssh-keygen
               use defaults
               will create:
                   .ssh/id_rsa (private key)
                   .ssh/id_rsa.pub (public key)

       put the public key in place:
           cd .ssh
           cat id_rsa.pub >>authorized_keys

       put the private key on the client and configure:
           scp id_rsa cuser@client:.ssh/id_rsa_server
           ssh cuser@client
           em .ssh/config
               Host tdm thedigitalmachine.com
                 Hostname thedigitalmachine.com
                 IdentityFile ~/.ssh/id_rsa
                 User m
               Host server
                 Hostname server.com
                 IdentityFile ~/.ssh/id_rsa_server
                 User suser

   all is full of light
Back up a linux system to a second bootable drive
Steps:
  1. We want to copy all files from the root drive to a new drive.
  2. We also want to update the boot menu to boot off the new drive.
  3. We also want to change /etc/fstab on the second drive to use the new root path.

These are the steps for backup of the dune box to the /spiceflow/2.0tb-newmovies/ drive. When we're done, we'll boot from that drive to prove we have a working standby system.

rsync does an excellent job of copying just what we need. Test it with this:

# a (archive mode -rlptgoD) v (verbose) x (don't cross filesystems) h (human-readable) n (dry run)
rsync -avxhn --progress / /spiceflow/2.0tb-newmovies/

Do the job with this:

rsync -avxh / /spiceflow/2.0tb-newmovies/

  sent 28.10G bytes  received 8.64M bytes  15.63M bytes/sec
  total size is 39.57G  speedup is 1.41

There was def some old stuff in there worth cleaning up:

/home/m/development/svn/mythtv...
/var/tmp
xbmc log files
etc

Next we fix /etc/fstab on the new drive to use the drive as root. Original config:

/dev/disk/by-label/d-g2-root        /                           ext3    noatime         0 1
/dev/disk/by-label/d-sp-20newmovies /spiceflow/2.0tb-newmovies  ext4    noatime         0 2

New config (remember tho, we lose the 2gb drive):

/dev/disk/by-label/d-g2-root        /root-hot-drive ext3    noatime         0 1
/dev/disk/by-label/d-sp-20newmovies /               ext4    noatime         0 2

Note: this never worked out for me due to my system's mix of ext3 and ext4. I'll retry once I migrate everything to ext4. Next, grub:

mount /boot
em /boot/grub/menu.lst

Orig entry:

title                                ----- linux-2.6.34-gentoo-r11_withext4
root (hd0,0)
kernel /boot/linux-2.6.34-gentoo-r11_withext4 root=/dev/sda4

Add a new "standby" entry under it - do a "df" to find the root:

title                                ----- ==STANDBY== linux-2.6.34-gentoo-r11_withext4 
root (hd0,0)
kernel /boot/linux-2.6.34-gentoo-r11_withext4 root=/dev/hda1

Then reboot to standby and see what we have... (no "latest" video library etc., but otherwise the same?)


git

Basic linux commands

Bash basics

Update gentoo kernel

Maintenance of my Gentoo boxes

Maintenance of my music collection

OS X basics

DOS basics

Update Boost

udev: Assign unique names to your devices

Automatically mount and unmount your devices

udev: Autorun programs when connecting your devices

Configure Eclipse

Configure Emacs

Configure MythTV

Basic MythTV plugin configuration