Tag Archives: virtual kernel

Ubuntu 10.10 + VMWare + Irssi

How small VM can you make if you are only going to use it to run Irssi in a screen?

OS: Ubuntu 10.10 x64 Virtual Kernel
Hypervisor: VMWare Workstation

Disk – no logs – 1.10GB is what my previous took, with samba, so probably less but 1.1 should be all right, don’t want it to run out of space either. Should probably partition /var/log into its own so that if that fills up (maybe after bruteforce ssh logins) then it doesn’t fill up the rest of /.
RAM –

  • turn off cron jobs
  • install virtual kernel

about the cron jobs, I just installed a ubuntu virtual kernel and only cron job running (as seen in syslog) is this:

CRON[9141]: (root) CMD (   cd / && run-parts –report /etc/cron.hourly)

Test 1

1.2GB disk
64MB RAM

Kernel panic – not syncing: attempted to kill init!
ctrl-alt-del in the VM doesn’t work, had to hard kill it :p
Reboot – same problem. It does this after selecting minimal virtual kernel and pressing install Ubuntu Server.

Test2

Increased RAM to 96MB and now it passed.
However, after selecting keyboard it still crashes. So 96 is also too little.

Googled around a little and found an article on Ubuntu.com that gives some insight.

For example: if you run out of memory, then it will swap. So if you are not running out of memory then it’s probably better to give it a little more to be on the safe side.

Test 3

Increased RAM to 128MB
Now it goes even longer.

Partitioning -> chose manual.
There is a device there ‘sda’ -> SCSI3. Mark that and hit enter. Say yes to create new empty partition. Then it creates a new space pri/log. Create new partition.

As size, type in: 100MB
Primary, beginning, default settings on the filesystem etc but mount point: /var/log. Then done setting up this partition.

Then we will create another partition for / (or the rest).

Like this:

ubuntu_partition right

ubuntu_partition right

The above does not include a swap space, and the installation complains that there is no swap space defined and that there may be problems if this is not configured during install.

Let’s see :)

** maybe Ubuntu is not the slimmest OS to install for this purpose. The guide I linked to above mentions a DSL – damn small linux. But we want a minimal server OS, not a desktop one. Maybe the new Debian 6 would be cool to try.

During install there was a dialogue about something being already on the disk.. and that this could cause issues. Maybe this was copied there from one of the previous tries with less amount of RAM. Went back and erazed this on each just to be on the safe side. Very slow though. About 1% / s. After this I went into each and set them to format instead. It mentions old installation files anyway. Proceeding. This happened twice? Three times now.. Maybe this is not going so well. Ok happened four times.

Hit Alt+F2 (and then enter to get the console) and then df -h. Nothing is over 20% except the SR0/cd-rom which is at 100%. Did a ‘more /var/log/syslog’ and at the end there are some ‘Out of memory’ things going on.

So there we go. 128MB is too little.

But here:  it says that 128MB is the requirement..

Test 4

I will try to install again and not mess up with the partitions.
1.2GB and 128MB again.
Going pretty well, looks like it’s stopped at 75% and “storing language”. Patience. Ok, 10mins later still there. Nothing about out of memory in /var/syslog. The Guest was behaving a little slow though when working the console.
Left it on over night and when I looked again the following day it was at the next step!

Installing openssh via the installation menu this time.
Taking quite long time this time as well. Like hours. 2 hours now. Nothing happening in syslog. Think I’ll give Debian a shot next Test.

In the meantime did Test 5. However 4 hours later, still configuring ‘language-pack-en-base’.

Now, approximately lots of hours later. It is at configure grub.

And yay, it finally boots!

user@irssi:~$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda1             1.1G  430M  606M  42% /
none                   54M  164K   54M   1% /dev
none                   57M  4.0K   57M   1% /dev/shm
none                   57M   36K   57M   1% /var/run
none                   57M     0   57M   0% /var/lock
none                  1.1G  430M  606M  42% /var/lib/ureadahead/debugfs
/home/martbhell/.Private 1.1G  430M  606M  42% /home/martbhell

And the size of the folder in Windows: 750 MB (787 341 312 bytes)

With 128MB ram there is maybe 10MB free and it swaps a little (just a few kB so far).

Test 5

debian-6.0.0-amd64-netinst
Using Debian 5 64-bit.

  1. graphical menu is seen, no advanced options used
  2. chose languages – look a lot like Ubuntu but there are some differences:
  3. After choosing a hostname it asks for domain. Put in WORKGROUP.
  4. Set a root account password (so no more sudoing – probably just add my user to the wheel/root group).
  5. and you have a few more options in the partitioning, like a separate /home partition
  6. then you get to chose a debian mirror (becuase I use the netinst). ftp.fi.debian.org is the one I chose
  7. you can participate in a “most used packages” survey
  8. software selection: graphical desktop, web, dns, ssh, laptop, standard system utilities. I chose SSH and standard system utilities.
  9. grub, then reboot and loading!

Internet works fine from the start. apt-get update; apt-get install irssi
Remember, here you have to log in as root to run ifconfig or apt-get.

It’s the same way in Debian as in Ubuntu to set static ip. Just edit /etc/network/interfaces / don’t forget you can just restart the networking services by ‘/etc/init.d/networking start’ instead of rebooting ;)
Now, I actually forgot to set minimal ram/disk for this one. So we have to do this again ;)

Test 6

debian-6.0.0-amd64-netinst
Using Debian 5 64-bit.
128MB RAM

One thing that’s cool about a VM is that you can resize the amount of RAM whenever (probably good to turn off the guest first). So how about just lowering it instead of installing a new one?

OK, so it now has 512MB. Going down to 64 in one go (listed as minimum in VMWare Workstation).

It’s swapping after just a few minutes with screen+irssi.

to sort by memory usage in top press SHIFT+m

biggest memory hogs (all over 1% – figures in bold) are :

1474 user 20   0 23388 6220 1572 S  0.0 11.2 0:00.25 bash
1503 user 20   0 50084 5228 3824 S  0.0  9.4 0:00.06 irssi
1470 root      20   0 70488 3280 2584 S  0.0  5.9 0:00.03 sshd
913 root      20   0  117m 1788  904 S  0.0  3.2 0:00.01 rsyslogd
1473 user 20   0 70488 1680  964 S  0.0  3.0 0:00.06 sshd
1502 user 20   0 25184 1472  992 S  0.0  2.6 0:00.01 screen
1546 user 20   0 19040 1300 1004 R 99.9  2.3 0:00.01 top
985 root      20   0 22392  712  512 S  0.0  1.3 0:00.00 cron
1233 Debian-e  20   0 44140  660  392 S  0.0  1.2 0:00.00 exim4
1472 root      20   0  5928  620  520 S  0.0  1.1 0:00.00 getty
1 root      20   0  8352  616  560 S  0.0  1.1 0:01.42 init
1277 root      20   0 49168  544  428 S  0.0  1.0 0:00.00 sshd

What I might be able to get rid of is rsyslogd and cron. But then again, if I were to connect this to the internet so I could access it and resume the screen/irssi from anywhere, I would want to keep track of what is happening on the machine.

user@debian:/var/log$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda1             3.8G  638M  3.0G  18% /
tmpfs                  28M     0   28M   0% /lib/init/rw
udev                   23M  140K   23M   1% /dev
tmpfs                  28M     0   28M   0% /dev/shm

Windows usage: 887 MB (930 816 000 bytes)

Summary

The Ubuntu Server 10.10 with the minimal virtual kernel took forever to install (maybe it would have been faster to have more mem during install and then lower when it’s done) and with 128MB it still swaps a little with only screen and irssi running. But it does use about 130MB or 200MB less space than the Debian6 guest.

The Debian 6 however runs OK with 64MB, swaps a little at that though so I would probably run this with 96 or 128MB just to be on the safe side if I were to run it.

File share from Ubuntu 10.10 with Windows 7 Client

Figured I would give this a shot and see how this is done in Linux.

Overview

1x Ubuntu 10.10 VM in VMWare Workstation. Installed with virtual kernel.
1x Windows 7 VM. All updates.

Not going to go through the installations in this post, just the domain/LDAP part. See previous posts for installation stuffs.

Found this article on ubuntu.com -> -> 10.10/serverguide/C/network-authentication.html .. But this does not exist anymore.

Whoa, quite a lot to do. Think I will read the manuals this time :)

Basically I think I just need to install and then configure Samba.
Because it has file-sharing and authentication/authorization.

So, first step will be to install Samba and try file-sharing.

File Sharing

sudo apt-get install samba

installs these:

The following NEW packages will be installed:
libavahi-client3 libavahi-common-data libavahi-common3 libcups2
libfile-copy-recursive-perl libgnutls26 libldap-2.4-2 libsasl2-2
libsasl2-modules libtalloc2 libtasn1-3 libwbclient0 samba samba-common
samba-common-bin update-inetd

After that I can run \\192.168.0.ip which is the IP of the VM running samba – it gives me a login prompt.

Uncommenting this in /etc/samba/smb.conf

[homes] comment = Home Directories
browseable = yes

Still asks for a password. Tried with user@ip – this seems to work. It shows a directory called “homes” but it doesn’t work to browse into it.

[2011/02/06 16:30:45.949726,  1] smbd/service.c:678(make_connection_snum)
create_connection_server_info failed: NT_STATUS_ACCESS_DENIED

Set ‘share’ and set the guest account = nobody  then I got this:

[2011/02/07 13:22:06.770082,  0] smbd/service.c:988(make_connection_snum)
canonicalize_connect_path failed for service foo, path /mnt/foo

Then what I did was this:

  1. created a directory called /samba
  2. sudo chmod +x /samba
  3. sudo chmod 777 /samba
  4. sudo chown nobody /samba
  5. add this to /etc/samba/smb.conf
  6. [foo] comment = foo
    path = /samba
    read only = no
    guest ok = yes
    guest only = yes
    browseable = yes
  7. security = share
  8. guest account = nobody

And then \\ip\foo and woopsie! I can both write and read :)

[2011/02/07 13:23:14.022980,  1] smbd/service.c:1070(make_connection_snum)
192.168.0.ip (192.168.0.ip) connect to service foo initially as user nobod

yay!

Ubuntu 10.10 Minimal Virtual Kernel + VMWare Workstation

To install Ubuntu 10.10 with a virtual kernel instead of the normal one = good, less stuff installed that you may not need.

  1. When setting up the install, do not use the easy install. Chose to install an OS later. Set up bridged/nat depending on which one you want.
  2. Add the install .iso to the CD-drive in the VM
  3. Select a language
  4. Press F4 (it didn’t work in the first screen)
  5. Chose – install a minimal virtual machine
  6. Install Ubuntu Server
  7. Chose language again
  8. Chose key map – (I chose English and had to browse to Finland)
  9. Asked to press some buttons, wanted Swedish (but have an English keyboard) so tried to press the right ones :p
  10. Then time zone Helsinki/Finland was found.
  11. Using default (whole disk, no encryption or lvm) for partitioning.
  12. set up users
  13. set up encryption on home dir
  14. proxy setup
  15. installing security updates automagically
  16. any extra packages (DNS, LAMP, Mail, OpenSSH, etc)? – I chose no, want to chose this myself later.
  17. yes I want grub (it finds only one OS on the virtual disk ;)

Then I see the login prompt! Obviously the easy-install in VMWare Workstation has a lot less steps :)

But on the other hand you could install OpenSSH directly through the install and then you do not have to log on to the VM via VMWare Workstation, but can do it via your favorite ssh program instead.

Post install

What I want installed every time after an uninstall.
After install it is a very very small installation.
Not even ‘man’ is installed.

sudo apt-get install openssh-server ntp nano

edit /etc/network/interfaces – configure static ip
edit /etc/ntp.conf – add time servers
edit ~/.bashrc – change colors in the prompt and add color

Kernel difference you can see when running uname: 2.6.35-22-virtual in comparison to 2.6.35-22-generic

There!

Now you can set up whatever you want on it! Of course you may want to do more things, set up iptables or you could use it like it is before the things I do after each install. You can use vi instead of nano/pico and use dhcp instead, depends on what you are going to do with your VM.