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Questions tagged [linux-kernel]

The Linux kernel is the operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software.

The Linux kernel is the operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software.

The Linux kernel is released under the GNU General Public License version 2 (GPLv2) (plus some firmware images with various non-free licenses[citation needed]), and is developed by contributors worldwide. Day-to-day development discussions take place on the Linux kernel mailing list.

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web server "task blocked for more than 120 seconds"

my web server is down every 2 days. it became unresponsive and I can only see the message below on the console. task **** blocked for more than 120 seconds. The only way to bring it up is resetting the server which is not good and I would like to…
masber
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Linux NFS hangs after about 15 minutes

I'm somewhat new when it comes to administering Linux and NFS, so please bear with me. We are trying to setup a small cluster at work. Currently the system is just 2 DELL high-end workstations, running CentOS 6.5. To make administering users and…
Maculin
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WANem doesn't boot after install

I'm using WANem live cd (based on knoppix) to perform network bandwidth tests. In order to keep the current configuration, I've installed it on hard disk (using the gui installation tool provided since v3) on VMWare ESX. The installation ended up…
Cramix
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Virtual Machines - Possible to Restore Replace Kernel without Rebuild?

I'm using Linux Virtual Machines (Wheezy, Linux Vserver), each with a desktop environment including Firefox. If a Virtual Machine where to be compromised (e.g., SQL injection) so the kernel is hacked and control has been seized of the VM (not the…
user185637
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find out which memory pages are owned by kernel

I can obtain a wonderful memory map of all processes with the Linux command pmap $(ps -A | awk '{print $1}'|grep -v PID) | sort | grep \^0 It looks like ... 00007fd6dbf45000 4K rw--- /lib/libnss_compat-2.11.1.so 00007fd6dbf46000 1524K…
Thorsten Staerk
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ext3 option on error doesn't work

I have a redhat server 5.8 with ext3 on top of lvm, i noticed ext3 has setting "Errors behavior: Continue" in the fs super block, from the man page of mount command i readed this errors=continue / errors=remount-ro / errors=panic Define …
c4f4t0r
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Fixed TCP payload Size

I have an aplication that need to have a fixed (516 byes) payload size in the TCP packet. The application itself can't be modified to adjust it settings, therefore i need to tune the TCP Buffer Size of the O.S.... As far as i know the TCP Buffer…
Bruno Araujo
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Capturing on loopback device on Ubuntu LTS: 15 Mbit of traffic and "x dropped packets"

I am trying to capture about 15 Mbit of traffic on the loopback device on Ubuntu LTS using tcpdump, and I am seeing dropped packets. The CPU is a freaking i7, and i have yet to see CPU usage go above 15% during the measurements i am trying to run.…
Tarnay Kálmán
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please explain my fio results - is O_SYNC|O_DIRECT misbehaving on linux?

I'm going mad over figuring out what the problem could be with one of our storage boxes. With a simple fio script I'm testing random writes using bs=1M and direct=1. The SSD is a Samsung 840pro attached to an LSI HBA (3Gbit/s ports). This is the…
Zoltán
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linux kernel configuration to filter multicast traffic based on interface

I have two virtual interfaces (eth0.2, eth0.3) in my PC. I am sending multicast data from eth0.2 to eth0.2. Multicast data is received in eth0.2 but also received in eth0.3, the other virtual interface. After a study I understand that Linux kernel…
arr
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RHEL 6.0 upgrading kernel from 2.6.32-71.el6.x86_64 to 2.6.32-358.2.1.el6.x86_64

[root@localhost ~]# rpm -ivh kernel-2.6.32-358.2.1.el6.x86_64.rpm error: Failed dependencies: bfa-firmware < 3.0.3.1 conflicts with kernel-2.6.32-358.2.1.el6.x86_64 [root@localhost ~]# rpm -qa |grep bfa bfa-firmware-3.0.0.0-1.el6.noarch Please…
abubacker
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Linux KVM: Troubleshooting dropped packets on a Windows Guest

virsh 0.9.10 Enterprise Linux 6.3 I have a Windows 7 guest running on the KVM host and am frequently seeing 25% loss when pinging other boxes on the same subnet. The first ping request times out, and the others usually succeed. How would I go…
user160910
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Scientific Linux: soft lockup on quad opteron system

After an impressive uptime of 550 days without trouble our quad opteron system turned into a corrupted system a few days after I mounted an nfs-share from a FreeNAS-box. Ongoing sessions remained active, but new logins failed since neither getting a…
user1980444
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Server freezes and suddenly load going very high

I'm on CentOS 5.7 and I get server freezes quite a lot and the logs show the following output: Dec 26 18:33:51 server kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Dec 26 18:34:00 server init: Switching to…
Imran Imtiaz
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CentOS 6.3 task blocked for more than 120 seconds

Recently have been getting Zabbix alerts about our mail system being unavailable, the uptime on the machine is 30+ days. I've been tracing the Zabbix logs and it looks like the communication between the Zabbix agent & server failed to respond in…
bmurtagh
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