Questions tagged [kernel]

In computing, the kernel is the main component of most computer operating systems; it is a bridge between applications and the actual data processing done at the hardware level. The kernel's responsibilities include managing the system's resources (the communication between hardware and software components).

In computing, the kernel is the main component of most computer operating systems; it is a bridge between applications and the actual data processing done at the hardware level. The kernel's responsibilities include managing the system's resources (the communication between hardware and software components).

Usually as a basic component of an operating system, a kernel can provide the lowest-level abstraction layer for the resources (especially processors and I/O devices) that application software must control to perform its function. It typically makes these facilities available to application processes through inter-process communication mechanisms and system calls.

Operating system tasks are done differently by different kernels, depending on their design and implementation. While monolithic kernels execute all the operating system code in the same address space to increase the performance of the system, microkernels run most of the operating system services in user space as servers, aiming to improve maintainability and modularity of the operating system.

Source: wikipedia

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Removing stubborn modules

I'm trying to programatically stomp on bluetooth on RHEL5. I've got the service stopped -- no problem. Also no problem on rpm -e for the associated bluetooth packages, bluez-*. ps -aef | grep -v grep | egrep -c '(sdpd|hcid)' returns zero , so I…
pboin
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Enable SMP on Debian i386?

I've been running a couple old HP machines on Debian for a while, and only recently noticed that they were only 'recognizing' and using one processor. cat /proc/cpuinfo only shows output for processor #0, same with top, etc. And when I pulled the…
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How to determine if a Debian upgrade updated the kernel

Let's say I have just done an aptitude safe-upgrade on a Debian system, but I was not paying attention so I did not notice if the kernel was updated or not. How can I now determine if there was a kernel upgrade and a reboot is in order?
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Server randomly freezes

Im facing a very strange issue, my debian squeeze freezes up always at night (Berlin, time). Here is what i get from a time and after doing this a few times, it becomes frozen and must be hard-reset. From /var/log/messages Dec 11 01:36:11 srv156…
PsySkeletor
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yum update kernel without removing old?

When I yum update it wants to remove the oldest of the 3 kernel I have and upgrade to a new. Is it possible to get yum not to remove old kernels?
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Redhat Linux Kernel what does GA mean?

When Redhat release a new major version such as 5.3, 5.4,5.5 .. the kernels seem to be referenced as GA , what does GA stand for ? example in this info doc http://www.redhat.com/archives/rhelv5-announce/2009-January/msg00000.html
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Kernel updates without rebooting

Similar to some of the topics touched on in this question, Is it important to reboot Linux after a kernel update?, I was curious if there was a way in which one could apply kernel updates to the system without rebooting. I know that there is a…
John
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TCP SYN Flooding Detection Method in the Linux Kernel

When the Linux kernel detects SYN Flooding it logs a message like: possible SYN flooding on port 80. Sending cookies Does anyone know the exact method that the kernel uses to detect this?
Kyle Brandt
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How do I build debian packages of kernel modules?

Specifically, I want to build a package for debian/lenny using the latest uvc drivers. I can compile and install them, but I want them packaged in the normal debian fashion. I imagine I want to use make-kpkg somehow, but I don't know how. …
Jayen
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Kernel Log "TCP: Treason uncloaked!"

On one linux server (Gentoo hardened), we are experiencing bursts of the following messages in dmesg from time to time: TCP: Treason uncloaked! Peer xx.xx.xxx.xxx:65039/80 shrinks window 4094157295:4094160199. Repaired. Is there anything we should…
hurikhan77
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How to get the latest kernel package on AWS EC2

I manage some EC2 instances running Amazon Linux (not sure what version), which need security patches. A lot of software was patched well, but we have stuck on the kernel upgrade. We are unable to use the latest kernel version as we preferred. What…
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How to switch from a custom Linux kernel to a distribution kernel

In my spare time, I help administer a hosted Debian Linux server that serves a variety of websites and hosts email for a few people. It doesn't see huge volumes of traffic, but of course we want to do things properly. However, when we first got this…
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AWS EC2 Status Check says "Instance reachability check failed " with kernel panic

I went to reboot my Centos 7 instance and then did a start/stop and now I get a status check error stating the instance is unreachable. I created a snapshot and image of the volume and recreated a new instance with an extra 4GB of space and I still…
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Tuning sequential disk reads for performance

I am reading a large file sequentially from the disk and trying to understand the iostat output while the reading is taking place. Size of the file : 10 GB Read Buffer : 4 KB Read ahead (/sys/block/sda/queue/read_ahead_kb) : 128 KB The iostat…
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CentOS 6.6 (Final) - yum kernel upgrade troubles

Well-being everybody, I'm a SysAdmin Junior managing 3 CentOS Virtual (Web)Servers, this morning I'm facing some troubles with package manager yum. As usual operation, this morning I've run the command yum update && yum upgrade, on one of the 3…
lese
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