Colin, my apologies for my late response. I found some time to play with
iSCSI again and used a fresh setup with final Ubuntu 9.10 server,
without much issues.

The problems i had appear to originate from the date Ubuntu 9.10 was
still in RC-phase; even after upgrading them as the final came out. I
just setup a completely new Ubuntu 9.10 server final iscsi install and
the initrd.img and vmlinuz written to the iscsi filesystem are indeed
usable and work for me. The problem as eymey explained, is getting that
initrd.img and vmlinuz (2 files) to the TFTP server used for booting.
I'll file a separate bug on that, as you requested.

I simply used an initrd i already had to boot the system, then copied
the /vmlinuz and /initrd.img files (which are symlinks and kept up-to-
date to the currently installed kernel/initrd.img) to the TFTP server
which pxelinux reads before the kernel is even started. An interum
workaround would be to put the initial two files of a blank installation
somewhere on the ftp server. I don't know about the 'dynamic' creation
of that /etc/iscsi/iscsi.initramfs file though. I booted with an initrd
from a different system, which would need to have different data in that
file, and it still worked. Possibly because its dynamically generated
when booting as it gets the data from pxelinux.cfg file which gives all
iscsi information, snippet:

  APPEND ip=bootp root=/dev/sda1 iscsi_initiator=X iscsi_target_name=X 
iscsi_target_ip=X iscsi_target_group=1 iscsi_target_port=3260 iscsi_username=X 
iscsi_password=X initrd=/tftp/initrd.img
(removed actual data by X for privacy)

I believe this data is used to generate the /etc/iscsi/iscsi.initramfs
file dynamicaly/automatically when the script activates upon boot.

I then upgraded using sudo apt-get update followed by sudo apt-get dist-
upgrade, and could copy the 2 files to my remote server again, and
booting worked fine. I created a small script i could run everytime
after installing ubuntu updates that involve kernel/initrd changes. I
simply run ~/updateiscsi and its copied to my remote server. So, i do
not have to generate an initrd each time after upgrading; thus the auto-
generated initrd.img is fine when using ubuntu 9.10 final.

So while it works, there are lots of rough edges:
- How to initially boot after installing; you need the initrd.img and vmlinuz 
files on the iscsi system but you can't get to that easily.
- After updating you need to manually synchronise your vmlinuz and initrd.img 
files to the TFTP server used for booting
- /etc/rc0.d and /etc/rc6.d hacks are still required for clean shutdown on 
iscsi-on-root systems
- /etc/network/interfaces must be manually created and set to static ip 
configuration; it doesn't appear to pickup the gateway information from the 
DHCP server initally
- If any local disks are present which you may or may not want to use as 
additional storage - not as root/system filesystem for Ubuntu - you need to 
change the pxelinux.cfg file to set root=/dev/sdb1 (for 1 local disk present) 
or to root=/dev/sdc1 (2 local disks present). Using UUIDs here probably won't 
work. Ideally, we would want a script that automatically checks which of the 
/dev/ entries is an iSCSI disk; and use that one automatically without 
requiring this parameter.
- As already talked about; only the server ISO allows iscsi-installation, not 
the alternative or desktop ISOs. I hope in the future, Ubuntu will be able to 
provide a 100% user-friendly ubuntu-on-iscsi installation without any hassle, 
without using the server install. My suggestion is to get the server install 
method to work 100% ok, and then work on improving the graphical installer in 
the desktop ISO. I strongly advise this course of action, since thin-clients 
are becoming very popular and it would be great if Ubuntu could contend in this 
area.
- Lack of any official / usable information on Ubuntu-on-iSCSI.

A lot of different issues with different solutions, to make diskless
ubuntu systems easier to setup and use. I do have some ideas/suggestions
for that, but do you want this to be a "master bug" and me to file
separate bugs on specific issues? Or do you want to close the bug,
because my initial problem with initrd.img files not booting, is now
resolved/invalid? That issue was when i initially used the initrd.img
file on a normally installed system, which did not include any
additional stuff for iscsi. So while the intended support for iscsi does
appear to work in Ubuntu 9.10 server final, it could be made much more
user friendly and hassle-free by automation, which is a
feature/enhancement request i guess. Please tell me how you like to move
forward with this new feedback.

-- 
iSCSI installation on root too complicated
https://bugs.launchpad.net/bugs/447377
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.

-- 
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to