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).

Filter by
Sorted by
Tagged with
0
votes
1answer
22 views

needs-restarting does not acknowledge the new kernel

Could somebody explain why my server has booted up using the latest kernel (v3.10.0-1127.10.1), yet the needs-restarting app says I still need to reboot to the new kernel? [user@domain ~]$ uname -r 3....
0
votes
0answers
15 views

Update Ububtu 16.04 kernel

I try to update Ubuntu kernel from 2.x to 4.x. I download new kernel and unpack it but when I want to upgrade it with this command sudo update-grub I get this error. root@server:~/4.11.2# sudo update-...
0
votes
1answer
21 views

pidstat: difference between task and process?

The pidstat command has options relating to tasks and others relating to processes (e.g. -C and -G). What's the difference?
0
votes
0answers
19 views

Run MongoDB with Unbreakable Enterprise Kernel (UEK) on Oracle Linux

I am running MongoDB v3.4.9 on Oracle Linux Server release 7.7 with the Unbreakable Enterprise Kernel (UEK) 4.14.35-1902.3.2.el7uek.x86_64 for testing purpose. UEK is not official supported on Oracle ...
0
votes
1answer
28 views

How to determine HugePages count?

I have a number of servers that we use as KVM hypervisor nodes. We want to enable hugepages and leverage this features for performance related matters. I have looked online on how to enable hugepages,...
1
vote
0answers
32 views

Linux kernel process consuming CPU 100%

On my RHEL7 VM, the kernel process migration/[some_number] cpu usage is 100% and continuously getting cpu soft lockup messages on the terminal. PID USER PR NI VIRT RES SHR S %CPU %...
1
vote
1answer
36 views

How are Unikernels different from Containers?

Unikernels are a new thing and I am having trouble understanding what their use cases are. Any use case I can think of is already served by the existence of Docker Containers. So what are Unikernels ...
0
votes
1answer
30 views

how to know if we reached the max value of fs.file-max

on our linux rhel servers fs.file-max set with 100000 sysctl -p | grep fs.file-max fs.file-max = 100000 from my understanding the file-max kernel parameter refers to open file descriptors, and file-...
0
votes
2answers
36 views

Understanding output from uname -a (kernel versioning and latest patch)

I'm trying to see if our servers are all patched, but the patching notation on these two RHEL servers is confusing me: hostA$ uname -a Linux hostA 3.10.0-1062.4.1.el7.x86_64 #1 SMP Wed Sep 25 09:42:...
-1
votes
0answers
18 views

dmesg + UDP: bad checksum. + rhel 7.x

from the dmesg we get very strange lines as [6484420.812643] raid6: using avx2x2 recovery algorithm [6484420.859086] Btrfs loaded [6484426.278636] nr_pdflush_threads exported in /proc is scheduled ...
0
votes
0answers
14 views

Linux autoreboot feature on kernel errors

When its recommended / not recommended to use the following autoreboot features for server VMs? kernel.panic kernel.panic_on_io_nmi kernel.panic_on_oops What about the risk for an corrupt filesytem ...
0
votes
1answer
32 views

linux hang + kernel messages about failed to assign mem

we have 5 Linux rhel machines , we noticed that all machines was hang with the same time from messages file we can se the following Dec 29 19:54:25 localhost kernel: pci 0000:ff:12.4: BAR 4: failed ...
0
votes
1answer
16 views

fsck on disk while Linux machine is up with runlevel N 5

we have linux machine , and we did the disk repair as the following umount /grid/sde fsck.ext4 /dev/sde e2fsck 1.42.9 (28-Dec-2013) /dev/sde: clean, 103867/1310720 files, 4725204/5242880 blocks this ...
0
votes
2answers
34 views

How to remove old kernel on Ubuntu operating system

I am wondering how can I do remove old kernel from Ubuntu operating system. Please refer image screenshot taken. Please advice. Many thanks. list of linux kernel
0
votes
0answers
27 views

beginner debian: system messed up?

I am a long term linux user, have been using SuSe in the 90s, then ubuntu, mint, and in the last years arch and manjaro. I am running a debian VM with virtualbox and I am a bit perplexed. I must have ...
0
votes
1answer
47 views

RHEL7.7 How do I run “debuginfo-install kernel” when using a local repo that is an iso mounted locally?

I want to use "crash" to look at the kernel core. crash /usr/lib/debug/lib/modules//vmlinux /var/crash//vmcore But /usr/lib/debug/lib is empty and it looks like that directory (debug libraries) is ...
1
vote
2answers
36 views

Centos 7x with 3.16 kernel

How do I get a 3.16 kernel? Veeam agent is not letting me backup btrfs with the 3.10, I grabbed 4.4 LT and system won't boot so scrapped that
0
votes
1answer
35 views

Is kernel 5.4.y supported for RHEL6?

We are trying to build 5.4.y for RHEL6/7/8, does anyone built the kernel 5.4.y for RHEL6? is it supported?
1
vote
2answers
40 views

repair file system by edit the fstab file

is it possible to run xfs repair by re-edit the fstab file? /dev/mapper/vg-linux_root / xfs defaults 0 0 UUID=7de1dc5c-b605-4a6f-bdf1-f1e869f6ffb9 /boot xfs ...
1
vote
1answer
55 views

How to disable Meltdown and Spectre patches in Centos 6?

I wondering how you can disable the Meltdown/Spectre patches in Centos 6? Various tutorials refers to Grub2 and recompiling, but in Centos 6, I do not have this. I can edit the grub.conf file in /...
0
votes
2answers
57 views

Is it possible to manually swap out a page by its virtual address?

Say, for a process, I know it has a page located at virtual address 0x42424242. I want to manually swap it out to the swap area. From user space I think it's hard to do so. I didn't find any related ...
0
votes
0answers
49 views

Virtualised Centos5.5 Server Having Kernel Errors

We have an old physical server that we can't lose, so I have virtualised it on VMWare. I have powered it up and am testing it. It froze earlier. In the kernel logs I found the following: Feb 20 08:22:...
0
votes
0answers
19 views

Is it possible to disable Transparent Huge pages on the fly?

In order to disable the THP We did the following on all 635 RHEL machines ( we have rhel 7.5 version ) This lines are from bash script that we runs on all machines step 1 [[ -f /sys/kernel/mm/...
0
votes
0answers
37 views

What is the suggested I/O scheduler to improve disk performance on HDFS file-system

What is the recommended I/O scheduler for HDFS file-system we have hadoop cluster with datanodes machines and we want to know the right configuration for I/O scheduler I/O scheduling in Linux ...
0
votes
0answers
40 views

Is it possible to prioritize writing over reading in disks?

We have a hadoop cluster, with data-node machines that use the HDFS file-system. We want to prioritize writing to disks over reading from disks. we have read the - Using the Deadline IO Scheduler ( ...
1
vote
1answer
692 views

Is there is any tool/way to find out why packet is getting dropped due to an arp cache full?

My developer hypothesis is packet is getting dropped at arp layer. We increased the default value of neigh.default.gc_thresh3 1024 --> 2048 and now everything looks good. But I want to understand is ...
1
vote
1answer
76 views

Change clock source in kernel stanza

I want to permanently change clock source in CentOS 7. I Found quite nice article here: https://access.redhat.com/solutions/18627 Permanently, adding clocksource= to the kernel stanza: title Red Hat ...
0
votes
1answer
151 views

Commands to Upgrade Kernel on CentOS 7

My current kernel is 3.10.0-957.1.3.el7.x86_64. I got to know about this by using the command uname -r. Now I want to upgrade my kernel version to 3.10.0-1062.12.1.el7.x86_64. I used the below blog ...
1
vote
1answer
97 views

Rechability of different interfaces without having a route in a seperate routing table

We're currently trying to route all packets from our guest vlan's (eth1.251) subnet trough a wireguard tunnel into the internet. To accomplish this we're using policy based routing with a rule to use ...
1
vote
2answers
178 views

cgroup rt support in Debian Buster (Kernel 4.19.0)

Is it possible to enable the cgroup rt support in Debian Buster (kernel 4.19.0) without recompiling the kernel? Perhaps with a grub configuration parameter? Thanks. Background: Docker logs this ...
0
votes
1answer
24 views

Ubuntu, freeze due booting

I have VPS with Ubuntu. Due system boot freeze now. I tried boot in recovery mode, but freeze too. I need data from this server, so is there way boot to system with SSH conection? Thanks. Update. ...
0
votes
0answers
22 views

no kernel log when plugging device

I'd want to get informations about and USB keyboard that I've just plugged on my Linux host (shared USB device from a Host, using vmware). Usually, I expect to see a message inside /var/log/kern.log, ...
0
votes
1answer
96 views

CE error on in Memory log

I Have HP server (DL360-G7) and on it run Centos7 + cPanel. in /var/log/message I see this error: EDAC MC0: 5450 CE error on CPU#0Channel#1_DIMM#0 (channel:1 slot:0 I change RAMs and memory slots in ...
0
votes
0answers
397 views

Apt is broken (unmet dependencies)

So basically whenever I try to install or remove anything, it says: You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies: libc-bin : ...
0
votes
1answer
19 views

Incorrect # of Free Hugepages in `numastat`

$ numastat -vm Per-node system memory usage (in MBs): Node 0 Total --------------- --------------- MemTotal 32464.24 32464....
0
votes
1answer
357 views

Inspect content of SLAB

Is there a way, preferably simple, how to inspect content of SLAB caches, especially dentry cache? I can imagine that this can be doable through kernel modules, but I highly doubt security would let ...
0
votes
0answers
44 views

centos 7 cant boot gnome after driver update stuck

I ran into a similar problem to CentOS 7 w/Gnome hangs on boot after Nvidia driver installation? after I followed https://gist.github.com/frengky/6bd5835491be40184760 to update my drivers. Except it ...
1
vote
1answer
24 views

kernel tunables for non privileged user

How can i permit non privileged user to set kernel tunables within specific limit. For instance to let user set hugepages up to 40 sysctl -w vm.nr_hugepages=40
1
vote
2answers
98 views

Booting an older kernel in Xen DomU when using pvgrub in Dom0

I'm having issues with the lastest kernel update in a Debian Jessie DomU, and want to boot it using a previous kernel. Dom0 is also running Debian Jessie, and is booting the DomU via PvGrub. I'm ...
0
votes
1answer
96 views

Is buddyinfo valid in virtual machines

Buddyinfo shows number of contiguous pages for each order available. Since virtual machine treats host's virtual memory as its physical memory does any kernel module allocating higher order memory ...
0
votes
0answers
24 views

Updating microcode with combined kenel/initramfs

I'm running a system that boots to a .efi image that contains the kernel and the initramfs (unified kernel image). It is based on centos 7, 64 bit, with an Intel processor. I know that with a separate ...
0
votes
0answers
14 views

FALLBACK logic needed for kernel Upgrade

The Ubuntu Linux system has one hard disk with three disks partition as below fdisk -l Disk /dev/sda: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors Sector size (logical/physical): 512 bytes / ...
0
votes
0answers
90 views

Random Ubuntu Server Crashes

For a few months now, I have been getting random crashes on a Ubuntu Server I have colocated. The server needs to be fully restarted to recover from this issue and when asked to investigate, the data ...
1
vote
0answers
227 views

ACPI Error: AE_AML_PACKAGE_LIMIT, Index (0x000000006) is beyond end of object (length 0x6) (20181213/exoparg2-396)

I'm strugglin to install any linux distro in a new Samsung Odyssey machine (NP800G5H-XT2BR) with success. After installation of any distro (ubuntu, fedora, debian), the computer: Freezes on Login ...
0
votes
1answer
100 views

cant counting all open files by lsof + lsof is hung

we are tying to count all open files by lsof lsof | wc -l lsof: WARNING: can't stat() fuse.gvfsd-fuse file system /run/user/42/gvfs Output information may be incomplete. but sill after 1 hour ...
0
votes
0answers
706 views

Downgrade to previous Linux kernel or libc6 version on OpenVZ (libc6 issue)

Recently i've tried to upgrade my server OS from Ubuntu 16.04 to Ubuntu 18.10, then i've found out that i'm on OpenVZ virtualization and it's impossible and stuck in the middle. Now apt-get install/...
1
vote
1answer
61 views

Determine Kernel Version based on File

I have a bunch of different Linux Operating Systems for many different architectures and for each of them I would like to determine their Linux kernel version. I can only access the filesystem but I ...
1
vote
0answers
196 views

Minimum Kernel configuration to use Azure accelerated networking

I am trying to add Azure accelerated networking support to a custom built Linux kernel. I enabled all the mellanox drivers, support for VFIO, infiniband drivers, vsock support and all of the hyperv ...
0
votes
0answers
58 views

How can I determine whether I'm vulnerable to SPECTRE/Meltdown/L1TF on Ubuntu

I'm running Ubuntu 18.04, and I have the following linux-image and intel-microcode packages: ii linux-image-4.18.0-17-generic 4.18.0-17.18~18.04.1 amd64 Signed ...
0
votes
3answers
63 views

How can I prevent a service from being stopped in Task Manager (Or McAfee EPO)

I have a service that should never be stopped and am looking into different ways to prevent stopping the process. This is a managed environment connected to Active Directory. Can any Windows-based ...

1
2 3 4 5
15