1
vote
2answers
42 views

order 4 allocation failure disaster

Some environment details first: Hardware: Intel Server Board S2600GZ 2 x Intel Xeon CPU E5-2620 64GB DDR3 RAM Intel RAID Controller RS2BL (LSI SAS2108) with 4TB LVM Volume made of SAS disks ...
0
votes
0answers
4 views

Unable to mount root fs over NFS [migrated]

I am attempting to set up the first (of many) Raspberry Pis running Pidora to boot from an NFS share. It is my goal to eventually place a dozen or more Raspberry Pis in the datacenter I use to power ...
1
vote
2answers
78 views

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, ...
0
votes
1answer
38 views

Can high disk cache usage lead to external fragmentation and ultimately to page allocation failures?

We're getting page allocation failures on a Linux server (3.2 kernel). We've been told the problem is directly related to the high use of the memory for cache; this would lead to external ...
-1
votes
2answers
70 views

All terminal windows suddenly disappear in Linux [closed]

Sorry in advance for the wall of text. I'm having a problem which is leaving me with very few clues as to what might be going on. Also, I apologize if ServerFault isn't the ideal place for this ...
4
votes
1answer
106 views

CVE-2014-0196 Vulnerability for CentOS

Trying to patch CVE-2014-0196 Vulnerability but yum can't find packages updates CentOS 6.5 (Final) Panel version: 11.0.9 Update #61 # uname -r 2.6.32-358.11.1.el6.x86_64 # yum update kernel Loaded ...
1
vote
2answers
111 views

ext3/ext4 physical block size view

I'm using a suse 11 server with xfs and using "xfs_info /srv" command i seen this. xfs_info /srv/ meta-data=/dev/mapper/vg01-srvvol isize=256 agcount=38, agsize=1964032 blks = ...
0
votes
1answer
22 views

“sock_sendmsg-error 22” error in RHEL

I am using RHEL 5.10 servers ( which are in cluster using some shared services). When I restart them using "init 6" or "reboot". the servers hang while shutting down, continuously showing the below ...
12
votes
2answers
484 views

Why does /proc/net/tcp6 represents ::1 as ::100:0

I was writing an utility to check /proc/net/tcp and tcp6 for active connections as its faster than parsing netstat output. As I dont actually have ipv6 enabled I was mainly utilizing localhost as my ...
1
vote
1answer
285 views

“show_signal_msg: N callbacks suppressed” then pegged at 100% and machine unresponsive

This happened on an Ubuntu 14.04 64-bit DigitalOcean Droplet: Apr 22 02:17:02 localhost CRON[32514]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly) Apr 22 03:16:59 localhost ...
2
votes
1answer
96 views

How can I make my own linux distro? [closed]

My question is bit off-topic or may be impractical. The thing is, on the web too many material available to download customized linux distro. But what if I want to make my own linux distro ? ...
0
votes
0answers
72 views

Cannot enable NMI Watchdog on HM65 Core i5

I'm trying to enable the NMI Watchdog on Linux on an AFL-12A-HM65 touch screen with an Intel HM65 Core i5 CPU. The user manual has an implementation for DOS (real helpful) but not for Linux. There ...
0
votes
1answer
122 views

What signal is being sent to an EC2 Instance on shut down?

When you terminate an instance-store pv instance through the AWS console or the API, what "signal" does it receive so it knows it has to gracefully shut down? First guess would be ACPI, but on boot ...
-6
votes
1answer
238 views

How to undo rm -rf? [closed]

How we can undo rm -rf command ? For example, I have Application folder. And I have remove it by rm -rf Application But it was my mistake and want to recovery or want that Application Folder. But ...
0
votes
0answers
53 views

ocfs2 with pacemaker cluster, space used 5.8G

I have a corosync+pacemaker cluster with suse 11 sp2, i created 1 million of files, using this script for testing the defrag problem #!/bin/bash i=1 until (false) do for k in `seq 1 100`; do ...
1
vote
1answer
904 views

Linux Kernel complaining about TSC when selected clock source is Hyper V

We are running RHEL 6 boxes on HyperV with Windows Server 2012. On a few on our RHEL boxes, I am seeing this error in /var/log/messages kernel: Clocksource tsc unstable (delta = -62519781 ns). ...
1
vote
2answers
52 views

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--- ...
1
vote
0answers
76 views

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 ...
4
votes
2answers
253 views

Linux: echo 3 > /proc/sys/vm/drop_caches takes hours to complete

I have a Thecus N8900 NAS, which is a Linux based file server, providing files via NFS to six clients. For some reason that Thecus support has yet to explain, it runs a script that checks ...
-1
votes
1answer
157 views

esxi 5 VMKernel and linux driver compatability mode [closed]

Many peoples around the web say, the esxi 5 kernel isn't based on linux kernel, but in the same times they say "ESX(i) includes a Linux driver compatability mode (drivers still have to be compiled ...
2
votes
1answer
55 views

Linux Kernel setup: is it good idea to enable everything in Cryptographic API?

There are several implementations for some algorithms, which use CPU instructions which may or may not be available on current system. Is it good idea to just enable (in kernel, not as modules) all of ...
3
votes
1answer
63 views

Linux kernel thread dependency graph?

I'm trying to benchmark a system with a software RAID-10 volume, backed by Fusion IO cards. Is it possible to display a Linux kernel thread dependency graph? I would like to know how all the ...
2
votes
0answers
215 views

Should I set rto_min for a route inside data center?

We have a few dedicated server rented in a data center with debian 7, kernel 3.2. We use one of those servers as a database server. The network between our application server and database server is ...
0
votes
0answers
159 views

KVM - task foo:1234 blocked for more than 120 seconds - howto change task scheduler

I recently installed a new Debian Wheezy server with KVM (the "KVM Host") then installed a Debian VM on the KVM (the "VM"), and got very bad performance on the VM. Looking through dmesg on the VM, I ...
3
votes
1answer
413 views

linux initcwnd and initrwnd via /etc/sysctl.conf

Folks, As we know, the 3.x kernels have higher TCP default connection values, such as initcwnd and initrwnd. For 2.x friends, is there a way to set these in /etc/sysctl.conf instead of the ip route ...
1
vote
3answers
382 views

High CPU usage in random IP/Port UDP DDoS

I have been getting these UDP floods with random IPs and ports. randomip:randomport -> myip:randomport 0 byte payload For some reason it is using a lot of CPU. Here is the results of perf top -e ...
1
vote
0answers
141 views

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 ...
0
votes
1answer
47 views

forcing linux kernel 3 to recognize cdrom as hdX

I have a problem with older version of anaconda linux installer. I have upgraded kernel in my distro, however, when this anaconda boot with this 3.4.52 kernel, can NOT find cdrom. As far as I ...
1
vote
1answer
408 views

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 ...
0
votes
1answer
57 views

Debian squeeze kernel update under Security Updates

Can someone explain what squeeze1 and squeeze3 designate at the end of a kernel name? For instance 2.6.32-48squeeze3 is showing up under Security Updates in Aptitude.
0
votes
1answer
137 views

Linux not freeing the file buffer when we execute rm or > (redirection) operator

I have one router which has embedded-linux with kernel version 2.4.22 running on it. I know its very old version but i have to deal with it. Please take a look at the free command output when i run it ...
32
votes
5answers
2k views

Intentionally cause an I/O error in Linux?

Is there anyway, with Linux, to purposely cause a block device to report an I/O error, or possibly simulate one for testing purposes?
-1
votes
1answer
245 views

understanding ip route show command on linux [closed]

I have a Windows 7 PC as host.The network details of my Windows PC are as follows. IP ADDRESS - 192.168.1.70 DEFAULT GATEWAY - 192.168.1.254 I have installed Virtual Box ...
2
votes
1answer
953 views

Cannot find network subsystem in cgroup on Ubuntu 12.04 LTS

I'm trying to use cgroups to limit a process's network bandwidth, as described in this answer. However, I am unable to find the "files" they refer to. I am using Ubuntu 12.04 LTS with cgroup-bin ...
0
votes
1answer
495 views

Debian Wheezy No longer booting. Freezes after setting kernel variables

My Debian (Wheezy) server has been running smoothly for a very long time with no indications of any problems. I had it running 24/7 so it was always on. The other day my power went out and when I ...
2
votes
2answers
309 views

Linux process swap usage is greater than the overall system swap usage

I have a strange problem that when I run top command it shows that some processes are using around 1.5GB of swap space but then the overall usage of the system swap is way to less to something around ...
1
vote
4answers
531 views

Linux high load with ImageMagick convert utility and server freezes (blktrack output attached)

I'm using ImageMagick to convert a JPG to TIF file, and I'm using the limit options for Imagemagick as below: /usr/bin/convert -limit memory 256 -limit map 512 subjectfile.jpg -colorspace Gray -depth ...
0
votes
1answer
304 views

CentOS server high load and server freezes

My server seems to get sudden high loads within second and when I run dmesg, following logs appear: INFO: task auditd:2185 blocked for more than 120 seconds. "echo 0 > ...
0
votes
2answers
796 views

XEN kernel shows less memory 32g

I have installed Oracle Enterprise Linux 64bit on the server with 64g of RAM. But the system detects just 32b of memory, here are the details: [root@oracle-node2 ~]# uname -a Linux ...
1
vote
2answers
175 views

using Linux as a bootloader?

I have an embedded device with a SPI connected flash. Basically this means the device boots its bootloader and Linux kernel from a small flash part. As the device boots, but before the root ...
2
votes
1answer
274 views

/proc/<pid>/stat children CPU time

I've been running the following command on my linux box: watch -d -n 1 "cat /proc/19866/stat" The pid above is a pid of Nginx's master process - I would expect the following fields to be changing: ...
1
vote
2answers
474 views

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 ...
-4
votes
1answer
69 views

Which Flavour of Linux comes with default kernel 3.4? [closed]

I was using centos but came to know it has restrictions to upgrade kernel version so looking for any other flavour with default 3.4 kernel version please suggest
0
votes
1answer
897 views

How can I confirm if my CentOS server supports multiple CPUs?

CentOS 5.8 | VMWare I've got a server running a hardened version of CentOS 5.8. I've been using a single CPU on it and am planning to add another (via vmware). When I run uname, I see SMP which ...
0
votes
1answer
524 views

How to stop a infinite running process(ztail) started by a ssh session after that session is closed

I have a peculiar problem. My server supports multiple ssh session simultaneously, so that multiple admins can manage it simultaneously. We have a command which calls ztail to show the compressed log ...
0
votes
1answer
225 views

what is occupying linux low memory

How can I find what is occupying my low memory on 32 bit Linux OS? cat /proc/meminfo |grep Low LowTotal: 812908 kB LowFree: 43340 kB Regards,
1
vote
2answers
4k views

Can't install kernel-uek-headers for currently running kernel

I have just created a VM in VMWare and installed a minimal install of Oracle Enterprise Linux 6.3. # cat /etc/oracle-release Oracle Linux Server release 6.3 It is running with the UEK kernel. # ...
0
votes
2answers
1k views

Kernel panic - not syncing - Attempted to kill init

I am using Linux 2.6.32-33-server #70-Ubuntu 10.04.3 as Data-Nodes and Name-Node in my Hadoop cluster, but one of my data node is down since morning. When i restarted that particular system it ...
2
votes
1answer
1k views

Limit the number of max threads used by a process in linux kernel

I think I have found something that I need from the Linux kernel that is not currently implemented. I need a way to set a max thread limit per process. Is this possible?
-1
votes
1answer
50 views

RHEL4 - 2.6.9-55 TO UPDATE 8 [closed]

I am having clearcase 7.0.1 application running on RHEL 4.0 (Paid & Unregistered)with the kernel version 2.6.9-55. When we ask the support redhat they said its not possiable because its not ...