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pxelinux setup

The pxelinux config is:


(yes, pxelinux.cfg is a directory).

also see /etc/dhcp3/dhcpd.conf for some pxelinux options.

working with the boot image

The booted servers don't have internet access (someone want to setup NAT on netbootyboxxy?), so to install packages on the netboot image:

chroot /exports/roroot /bin/bash

Then run aptitude or whatever it is you want to do.

accessing booted servers

They all run ssh and use the ~/.ssh/fish ssh key on netbootyboxxy.

if they are doing the hardware inventory then they will hit apache to get their MAC address so you can work out their ip to ssh to (the dhcp or tftp logs work too)

  • ssh -i ~/.ssh/fish root@10.192.38.something

The tw_cli command line tool can reconfigure the megaraid controllers without having to go into the bios, i'm not sure it's any faster tho (it's in roots home dir on the netboot image).


/c0 show

to see whats going on on the controller

delete units with:

/c0/u2 del

(to delete unit 2)

and then to create JBOD disks:

/c0 add type=JBOD disk=5

the number after the 5 is the port number (p5 etc).

hardware info files

The script is just rc.local

Files dumped under /export/records/mac-address/

biosdecode biosdecode output, not very useful
dimms output of the decode-dimms script, relies on the i2c modules working properly, which is quite motherboard specific, useful when it works tho.
dmidecode dmidecode output, should have motherboard model and bios date etc..
dmraid-b lists block devices that dmraid finds
dmraid-r lists raid devices that dmraid finds, if any.
env.txt dump of the environment, useful for debugging
hwinfo hwinfo dump, includes loads of debugging info, but some useful stuff in there.
lshw human readable lshw output
lshw-xml xml format dump of lshw
smartctl-a-:dev:<disk> smartctl -a for the disk - lots of info
smartctl-H-:dev:<disk> smartctl -H for the disk, smart pass/fail


  • make the bootimage readonly (I looked at nfsbooted, but wasn't sure it did what we wanted)
  • look at adding dwipe (the wipeing component of dban) to the image
  • write scripts for report generation of the hardware we have for ebay listing purposes.
  • add an seti@home option
  • and maybe povray
  • workout why smartctl (?) sometime core dumps with -H
  • XXX find a way of mapping the current machine catagory/number to the dumped records.
    • Not that hard. Just sort by mtime and don't boot them all at once: [1]
  • does pxe tell us if the machine is 64bit capable? - No, sadly.
  • add a 32bit image, partly done, but not working yet
  • add mcelog :