What do these SATA errors mean?

Posted on by

For SATA drives, occasional transmission problems are expected even on otherwise pretty healthy systems. No need to worry about it too much unless the problem repeats itself a lot.

via What do these SATA errors mean / kernel 2.6.25.6 (DRDY ERR/ICRC ABRT) | Linux | Kernel.

This error occurred on the drive using the hot swap cage.  I wonder if perhaps the circuitry on the cage is iffy.  The circuit board on that cage is about the simplest board that can be designed — it just maps wires from one pin connector to another — that’s it.

Perhaps the centos install is OK after all.  It’s intermittent which is bad.  Looks like it might pay to use higher quality hot swap cages.  Tomorrow I’ll try another brand and investigate this further.  Here’s another pertinent point.  I’m seeing this exact same error.

> 51/84:f8:47:dc:35/00:03:02:00:00/e0 Emask 0x10 (ATA bus error)
> Jun 11 05:46:23 p34 kernel: [ 1445.288637] ata12.00: status: { DRDY ERR }
> Jun 11 05:46:23 p34 kernel: [ 1445.288639] ata12.00: error: { ICRC ABRT }

That’s your drive reporting that it saw transmission error on the wire.

Authentication Token Manipulation Error

Posted on by

if u are running shadowed passwords it might be theres no entry for this user. make a backup of /etc/shadow, delete /etc/shadow and convert /etc/passwd using pwconvert.same goes for /etc/groups.

via Authentication Token Manipulation Error.

I got this error when logging in as root into a system that I think was badly installed (by me).  Anyway, this fixed that problem.  I found it interesting that this came up #1 on the google search and it’s an entry dated May 2001.

Note: The linux command pwconv replaced pwconvert sometime during these last ten years.

Note2:  Here’s a more modern (3 years old) explanation tmhat I found useful.

Note3: I still had to do a complete reinstall since a lot of things went haywire.  I probably shouldn’t have been playing with hot swapping while the install was in progress.

Update:I don’t think the kernel likes this motherboard.  Second install failed.  Have to resort to compiling a kernel by hand.  What started out as a simple hour long task will now take all night.

Finding linux distro release info

Posted on by

Fedora Core: /etc/fedora-release

Red Hat: /etc/redhat-release, /etc/redhat_version (rare)

via release-files.

I got confused between two Centos VMs.  I had thought one Centos VM that I have running DNS was Centos 5.4 and the new one was Centos 5.6.  When I saw that they both used a 2.6.18.* kernel I got confused.  Fedora Core is using 2.6.35 and greater.  This led me to check the distro version upon which I didn’t get it out of uname -a or dmesg.  Searching the intertubes and I got the above answer.  Apparently the VM I thought was 5.4 is really 5.5.

It is interesting that Centos, which tracks RHEL, doesn’t make too many radical changes to the kernel.

Update: It should be noted that I wouldn’t have noticed the kernel versions had I not tried to compile and install my own kernel.

Darwin Streaming Server

Posted on by

Welcome to Darwin Streaming Server, the open source version of Apple’s QuickTime Streaming Server technology that allows you to send streaming media to clients across the Internet using the industry standard RTP and RTSP protocols. Based on the same code base as QuickTime Streaming Server, Darwin Streaming Server provides a high level of customizability and runs on a variety of platforms allowing you to manipulate the code to fit your needs.

via Darwin Streaming Server.

Xen – KVM – Linux – and the Community

Posted on by

KVM is a type-2 hypervisor built into the Linux kernel as a module and will ship with any Linux distribution moving forward as no work is required for the Linux distributions to add KVM. Having a virtualization platform built-in to the Linux kernel will be valuable to many customers looking for virtualization within a Linux based infrastructure; however these customers will lose the flexibility to run a bare-metal hypervisor, configure the hypervisor independent of the host operating system, and provide machine level security as a guest can bring down the operating system on KVM. Xen, on the other hand is a type-1 hypervisor built independent of any operating system and is a complete separate layer from the operating system and hardware and is seen by the community and customers as an Infrastructure Virtualization Platform to build their solutions upon.

via Xen – KVM – Linux – and the Community – blog.xen.org.

Configure the GRUB boot loader

Posted on by

Adding a single user mode option to the GRUB menu

password –md5 $1$U$JK7xFegdxWH6VuppCUSIb.

default 0

title Red Hat Linux (2.4.9-21)

root (hd0,0)

kernel /vmlinuz-2.4.9-21 ro root=/dev/hda6

initrd /initrd-2.4.9-21.img

title Red Hat Linux (2.4.9-21) single user mode

lock

root (hd0,0)

kernel /vmlinuz-2.4.9-21 ro root=/dev/hda6 s

initrd /initrd-2.4.9-21.img

via Configure the GRUB boot loader.

Installing and Configuring Fedora Xen Virtualization

Posted on by

There are two common approaches to virtualization – full virtualization and para-virtualization. Full virtualization provides complete abstraction between the hardware and the guest operating system. In this scenario, the guest operating system is provided a complete virtual physical environment in which to run and, as such, is unaware that it is running inside a virtual machine. One advantage of full virtualization is that the operating system does not need to be modified in order to run in a virtualized environment. This means that proprietary operating systems such as Windows can be run on Linux systems.

Disadvantages of full virtualization are that performance is slightly reduced as compared to para-virtualization, and some virtualization platforms, such as Xen, require CPUs with special virtualization support built in (such as Intel-VT and AMD-V).

via Installing and Configuring Fedora Xen Virtualization – Techotopia.

The Linux Virtual Server Project – Linux Server Cluster for Load Balancing

Posted on by

What is the Linux Virtual Server?

The Linux Virtual Server is a highly scalable and highly available server built on a cluster of real servers, with the load balancer running on the Linux operating system. The architecture of the server cluster is fully transparent to end users, and the users interact as if it were a single high-performance virtual server. For more information, click here.

The Linux Virtual Server Project – Linux Server Cluster for Load Balancing.