I have read an article (not in English) on how to protect a server against SYN flood attacks by modifying some directives in sysctl.conf. That article has a sentence like: “it’s possible to recompile kernel with some options to improve protection against the SYN flood”. I’m sorry if my question is too general but could you point out to me which kernel options it may be referring to? I downloaded the kernel and looked through [...]

I’m try to upgrade a debian system to 2.6 64 bit kernel with the command aptitude install linux-image-2.6.32-5-amd64 which works fine. The system reboots, /vmlinuz -> boot/vmlinuz-2.6.32-5-amd64 all good however uname -a returns Linux hostname 2.6.32-5-686 #1 SMP Sun May 6 04:01:19 UTC 2012 i686 GNU/Linux Am I missing something or is this correct? Asked by mark In case anyone else suffers this problem, I just needed to force grub to reconfigure (I had assumed [...]

Hi we have a Windows Server 2008 R2 server that has been having issues lately. Right at the same time as most of the issues started happening I noticed that there are lots of exceptions in the logs for KERNELBASE.dll – This doesn’t look good, I’m wondering if anyone out there can help me interpret this event from the event log? Thanks. Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7afa2 Faulting module name: KERNELBASE.dll, [...]

I have downloaded latest ubuntu server edition but after installing its showing kernel of 3.2.0-23 Generic kernel,which is a development version. So how can i change to stable release with out compiling?? Asked by Kevin Parker To put this stuff in a real answer: You have a production version. Linux version numbering has changed a lot and the odd/even method haven’t been used since 2.6.0 has been published years ago, as there are no development [...]

I’ve got a (TCP) server that handles a big number of new connections per second (1000 – 5000). This causes syn cookies to be send: kernel: possible SYN flooding on port 2710. Sending cookies. Syn cookies aren’t that bad (in this case), but how do I avoid this. What app or kernel knobs can I turn? Documentation on this appears to be very scarce. The kernel is Linux 2.6.32 x64. Asked by n/a The syncookies [...]

Debian is running 2.6.32-5. Recent kernels seem to have addressed some kernel soft lockup issues, I’d like to try them. Although… the patches don’t seem to be in the Debian-stable repository. # dpkg -l linux-image-2.6.32-5-686 Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Description +++-======================-================================================================================== ii linux-image-2.6.32-5-6 2.6.32-44 Linux 2.6.32 for modern PCs Why is the Debian “Version” 2.6.32-44 when the kernel is 2.6.32-5 ? What does upgrading to Debian version 2.6.32-45 (of [...]

Recently I have come across a security module for the Linux kernel called Linux-VServer which allows you to virtualize many things and “partition” the OS to reduce the effects of a compromise. I was surprised to see that it required a re-compilation of the kernel as most of these types of things are simply modules that can be loaded at run time (selinux, apparmor). My problem with recompiling the kernel to enable Linux-VServer is I [...]

I need to support the realtek rtl8139 network card – is this included in modern (> 3.0) linux kernels? do I have to load any modules or install anything? Asked by Michael Neale The Realtek is a fairly standard adapter and has been in the mainline kernel for a long time. The driver/module is 8139cp.ko. The device should be auto-detected on a modern Linux distribution. Answered by ewwhite Check more discussion of this question. Bookmark [...]

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 [...]

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 Asked by AndyM General Availability – i.e. stable and ready to use and be supported. Answered by Chopper3 Check more discussion of this question. Bookmark on Delicious Digg this post Recommend on Facebook share via Reddit Share with Stumblers Tweet about it [...]