Daz’s bits and bobs

I’ve had some problems since my upgrade to virtualbox 2.2.0 on OpenSolaris. After some time all of my linux boxes seem to just die. The virtual machine just stops responding. Strangely there was no problem with my windows vms after the update.

From what i can tell it looks like the upgrade turned off “IO APIC” – this is the bit that seemed to cause the problem. Re-enabling this on all of my linux boxes seems to have fixed the problem. I’ll continue testing for another week and update this post if any problems re-occur.

Updated : 01/09/2009

Here is a bit more on IO APIC from the virtualbox wiki…  (from a windows perspective)
http://www.virtualbox.org/wiki/Migrate_Windows

The hardware dependent portion of the Windows kernel is dubbed “Hardware Abstraction Layer” (HAL). While hardware vendor specific HALs have become very rare, there are still a number of HALs shipped by Microsoft. Here are the most common HALs (for more information, refer to this article: http://support.microsoft.com/kb/309283):

Hal.dll (Standard PC)
Halacpi.dll (ACPI HAL)
Halaacpi.dll (ACPI HAL with IO APIC)

If you perform a Windows installation with default settings in VirtualBox, Halacpi.dll will be chosen as VirtualBox enables ACPI by default but disables the IO APIC by default. A standard installation on a modern physical PC or VMware will usually result in Halaacpi.dll being chosen as most systems nowadays have an IO APIC and VMware chose to virtualize it by default (VirtualBox disables the IO APIC because it is more expensive to virtualize than a standard PIC). So as a first step, you either have to enable IO APIC support in VirtualBox or replace the HAL. Replacing the HAL can be done by booting the VM from the Windows CD and performing a repair installation.

Updated : 5/09/2009

I’ve had even more problems with opensolaris crashing completely after upgrading to the newer versions of virtualbox (3.0.4), and have since reverted back to 2.2.0 which has fixed alot of the hanging issues i have encountered

If you are having problems starting apache on a non-standard port you might find that the problem is related to selinux.

Type this command to check to see what http ports are currently allowed;  (remove filter to show all rules)

semanage port -l|grep http

To add another port type the following (with the port you wish to add etc);

semanage port -a -t http_port_t -p tcp 81

If you want to disable selinux completely then go into /etc/selinux/config and set selinux=disabled. Save then reboot.

Setting up LAMP on fedora 11… First install the required modules.

yum install -y httpd.i586 mysql.i586 mysql-server.i586 php.i586 php-mysql.i586 php-gd.i586

Next i’m copying my web source from another linux machine. I’ve run these commands from the destination machine…

cd /var/www/html

rsync -ave ssh 192.168.9.10:/var/www/html/ .

Now my mysql data…

cd /var/lib/mysql

rsync -ave ssh 192.168.9.10:/var/lib/mysql/ .

Accept the certificate and enter the source root password. Next fire up the services…  I usually just go into “setup” then “system services” and enable both httpd and mysqld

Reboot. Done

Still my favourite light and fast web proxy is Squid. Its very easy to setup and get running on almost all flavours of linux. You can find it here http://www.squid-cache.org/ but will probably find it in your local package manager…

This is for more my own reference… as i don’t think too many people have the need for a transparent proxy. You only need one NIC configured on your VM / machine as its most probably on the same subnet as your dsl etc…

1. Setup squid working as a proxy first!

Set the default gateway on the NIC to your router. I also added a default route 0.0.0.0 sub 0.0.0.0 to the router also just in case the default route didn’t work. But seemed to!

Setup DNS! remember you should be able to resolve a name to an IP without issues (can cause most of the problems) Point your default DNS to your router (most have built in DNS forwarders), else you can just use your ISP’s DNS’s

2. Change the squid.config to have the necessary changes to act as a transparent proxy;

nano /etc/squid/squid.conf

This redirects standard tcp requests to 3128 (squid’s port)… transparent to user

4. Ensure that IP forwarding is ENABLED;

change ip_forward from 0 to 1 (usually a txt file somewhere with 0 in it), do a search and you will find it… most probably in the ipv4 directory. This way all 443 (https and other apps) can forward to the web without issue…

echo 1 > /proc/sys/net/ipv4/ip_forward

Should be it…. else good luck!

Update: I have done an updated post about configuring open solaris as a transparent proxy here : http://sigtar.com/2009/04/22/opensolaris-configuring-squid-as-transparent-proxy/

In Windows i use robocopy…

This is the syntax to move from one location to another…  (i like how robocopy uses UNC paths)

robocopy \\192.168.9.70\videos \\192.168.9.101\videos /move /e /r:2 /w:10
robocopy \\192.168.9.70\software \\192.168.9.101\software /move /e /r:2 /w:10

Note: if you are in a production environment execute the above without the /move for the first run!, if all goes well then run again with the /move switch (this reduces the downtime if you are swapping out servers). i.e. run the first pass before the change window.

/e moves all directories including empty ones.

In Linux i use rsync…

i typically mount a smb share on a windows host…. (you must have cifs client on linux first)

mount -t cifs -n //192.168.9.70/backup /mnt/backup -o username=user,password=mypassword

then use rsync for the copy work…

rsync -rcav /etc/ /mnt/backup/etc/

if your after linux to linux copying then rsync is also the best way to do it (via ssh), logon to your destination box via ssh and run this from your distination diretory..

rsync -ave ssh 192.168.9.10:/var/lib/mysql .