Entries Tagged 'Linux' ↓

Here  some results from testing I did in August 2009 on  KVM with the three different disk image drivers. First a single disk system running Ubuntu x64 9.04:

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I haven’t seen much yet to confirm this deal, but if it does happen next week it mark an interesting change in course.  The thing that would interest me greatly would be zfs on linux – with Sun owned by IBM and their investment in Linux it might lead to a reconcilation between Sun and Linux licenses.  While Solaris has come a long way in the last couple years, but the only reason why I use solaris is zfs.  Linux is still a much more flexible, effective and deployable solution. 

I tried several methods last night including Unetbootin, and this is the one that worked best.

• Using Windows to prepare USB install of Ubuntu 8.10
• Preparing Files for USB Memory Stick Booting

Basically copy the ISO on the USB root directory, add vmlinuz and initrd.gz from main/installer-i386/current/images/hd-media/. Then add syslinux.cfg with:

default vmlinuz
append initrd=initrd.gz

If you have boot problems you might also need to run install-mbr /dev/sda from the mbr package.

I keep smacking into this issue. So a couple notes to myself for future reference.

• Tinydns / DJBDNS on Ubuntu Hardy Heron
• upstart breaks inittab

Before install touch /etc/inittab and afterwards add this to /etc/event.d/svscan:

start on runlevel 3
start on runlevel 4
start on runlevel 5

stop on runlevel 0
stop on runlevel 1
stop on runlevel 6

respawn
exec /usr/bin/svscanboot

Lanuchy is a quicksilver-like key stroke application lanucher for linux and windows. Very cool.

Shared subtrees – in depth look at bind mounts.

Windows* client CIFS behavior can slow Linux* NAS performance:-

We have compared the performance of Windows* and Linux*-based CIFS* (Samba*) servers for digital media applications and found that the ext3*-based Linux server’s throughput was up to 53% lower than the Windows server’s–although both used identical hardware (Figure 1). An XFS*-based Linux server had roughly the same performance as the Windows server. Our investigation shows that the difference lies in the filesystem allocation and handling of sparse files. In particular, the Windows client makes an assumption that the CIFS fileserver uses NTFS*, a filesystem that assumes files will be data-full (not sparse). This contradicts a fundamental assumption of ext3–that files are sparse–and leads to fragmentation of files and degraded performance on ext3. Further, we’ve seen this behavior manifested for a broad range of media applications including iTunes*.

Couple useful articles from Andy Millar.

• Concise and clear explaination of linux load averages.
• Bug fix suggestion for VMware server which can hang on installation. Remove the floppy device. I’ve got another issue where a linux vm on vmware server hangs on startup and I’ll have to try this.

Occansion in Linux when running a VPN you want to generate traffic from the VPN server node. By default Linux uses the IP of the interface used to route a package. The might often complicated the routing tables required at client networks.

A solution to fix this issue is to use Linux source/policy routing. For example, for node with IP 192.168.10.1 and VPN server IP 172.29.148.1, route to subnet 192.168.9.0/24 out 172.29.148.1 via 172.29.148.2 with src (source) IP 192.168.10.1:


sudo ip route add to 192.168.9.0/24 src 192.168.10.1 via 172.29.148.2


You have you the following error:


kernel: XFS: Filesystem lvm(58,2) has duplicate UUID - can't mount


Using the following:


mount -o ro,nouuid /dev/vg/lvsnap /mnt/


Thanks too.