Browsing articles tagged with "linuxkernel - Admins Goodies"
Dec 13, 2012
tom

Where are the acpiphp and pci_hotplug kernel modules for KVM hotplug in CentOS/RHEL?

On the this how-to I read the following: I loaded the following modules to get pci hotplug working: acpiphp pci_hotplug You can either add these to your distro’s module list to load on boot, or run a command like this. for m in acpiphp pci_hotplug; do sudo modprobe ${m}; done However, on CentOS 6.3 and Red Hat Enterprise Linux 6.3 this modules does not exist, on Ubuntu Server and Debian 6 it does. Why? Any […]

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Oct 11, 2012
tom

Debian on Hyper-V

I installed Debian with kernel 2.6.32-5-686 on a Hyper-V virtual machine. I had to add a legacy network card. I follow this tutorial http://www.yusufozturk.info/linux-server/debian-2-6-36-kernel-upgrade-for-hyper-v-client-drivers.html to add Hyper-V driver but when I reboot with the new kernel i got this error: BLKVSC_DRV: blkvsc_probe() ERROR!! register_blkdev() failed! ret -16 And at the very first boot log (that i can not copy because i did not find it in dmesg or boot log) i see a mount /dev […]

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Oct 10, 2012
tom

yum security update – message indicating kernel version not up to date

Running yum –security check-update returns this message: Security: kernel-3.x.x-x.63 is an installed security update Security: kernel-3.x.x-x.29 is the currently running version I already ran the yum security update on the kernel, but it looks like it didn’t change the version running on the system. What needs to be done to make it run the new kernel? Are there any concerns about why it didn’t change during the installation process? The yum log just shows installed […]

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Sep 7, 2012
tom

How can I get APT to “ignore” a package?

I am running a VPS using Debian unstable with this kernel version: 2.6.32-274.7.1.el5.028stab095.1 I just upgraded my packages and for some odd reason APT wants me to install linux-image-3.2.0-3-amd64, which is strange, seeing as I can’t modify the kernel as it’s a VPS. I tried installing it anyway, but as I suspected it didn’t work: root@youmu:~# apt-get upgrade Reading package lists… Done Building dependency tree Reading state information… Done 0 upgraded, 0 newly installed, 0 […]

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Jun 23, 2012
tom

Making directories visible only by owners

I am in the process of creating a secured shared hosting and, between the hosting features, I want to give SSH access. I’ve already chrooted the users via SSH, FTP and PHP (using PHP-FPM), and would like to improve the hosting’s security even more. I want the users not being able to see each other’s processes, and I’ve already patched the kernel to do so (this way): it works in top and ps, but the […]

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Apr 27, 2012
tom

Compiling linux kernel – `make install` asks for LILO. Now what?

So I am following this guide to compile my custom kernel – http://library.linode.com/linode-platform/custom-instances/pv-grub-custom-compiled-kernel#sph_compile-and-install-the-kernel So far so good, but I hit a little road block with make install. AS arch/x86/boot/header.o LD arch/x86/boot/setup.elf OBJCOPY arch/x86/boot/setup.bin BUILD arch/x86/boot/bzImage Setup is 15328 bytes (padded to 15360 bytes). System is 5097 kB CRC c20c9369 Kernel: arch/x86/boot/bzImage is ready (#2) [root@li280-195 linux-3.3.3]# make -j3 modules make[1]: Nothing to be done for `all’. CHK include/linux/version.h CHK include/generated/utsrelease.h CALL scripts/checksyscalls.sh CC [M] drivers/scsi/scsi_wait_scan.o […]

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Apr 26, 2012
tom

Learning how to build my own linux kernel

Reference – http://www.linode.com/wiki/index.php/PV-GRUB#Building_Your_Own_Kernel In order to work with Xen, a number of options that must be selected: CONFIG_PARAVIRT_GUEST=y CONFIG_XEN=y CONFIG_PARAVIRT=y CONFIG_PARAVIRT_CLOCK=y CONFIG_XEN_BLKDEV_FRONTEND=y CONFIG_XEN_NETDEV_FRONTEND=y CONFIG_HVC_XEN=y CONFIG_XEN_BALLOON=y CONFIG_XEN_SCRUB_PAGES=y Where exactly do I specify these configuration? I have done these steps so far:- wget http://www.kernel.org/pub/linux/kernel/v3.0/linux-3.3.3.tar.bz2 tar -xf linux-3.3.3.tar.bz2 cd linux-3.3.3 make menuconfig make menuconfig brings me to the ncurses “GUI” but there are so many options I am completely lost…. Any suggestions how I should proceed? Asked by […]

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Apr 21, 2012
tom

Do i have to install vmware tools on ubuntu server

its a bit silly Question, I was thinking since i have some spear HW to install ESXi free edition and allow some external users to use prebuild ubuntu 10.04 servers. since with kernel updates etc etc the vmware tools have to be re installed i was thinking to give the server without tools. So the client wont have to be afraid to do upgrades. what is your opinion? Asked by Elgreco08 VMware Tools should be […]

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Mar 28, 2012
tom

Redhat Kernel patching advice

An audit has pointed out that a RHEL server I manage has not had the latest kernel patches applied. I’m confused about kernel patching and within RHEL in relation to RHEL dot releases i.e 5.2 , 5.3 ,5.4 ….. Can someone answer these questions ? If I want to stay at a dot release of RHEL, say 5.4, can apply just updates to the 5.4 kernel or will applying kernel updates bring the server to […]

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Mar 16, 2012
tom

How can I tell the kernel to free cached memory during memory allocation request instead of the OOM killer terminating the application

I am running Ubuntu 10.04 with the below kernel version Linux ip-10-0-1-119 2.6.32-343-ec2 #45-Ubuntu SMP Tue Feb 14 18:18:17 UTC 2012 x86_64 GNU/Linux The memory status shows that the cache is using the maximum share of the RAM. ubuntu@ip-10-0-1-12:~$ free -m total used free shared buffers cached Mem: 7702 7657 44 0 24 6137 -/+ buffers/cache: 1494 6207 Swap: 0 0 0 I understand that the OS manages it automatically and keeps the maximum share […]

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