Linux
Discussion List
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OCI: How to stop unwanted firewalld processesApplies To: Oracle Cloud Infrastructure Linux x86-64 Goal: This document outlines the steps required to stop any unwanted firewalld processes Symptoms: The firewalld.ser… -
How do I reset an instance to default image?Summary: Resetting an instance to default supplied image Content (required): I created an instance with image imported from oracle supplied image for Ubuntu. The instanc…
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OSMH: Instances failed with error YUM Timeout "(28, 'Operation timed out after 30001 milliseconds)"APPLIES TO OSMH On-Prem SYMPTOMS "yum repolist" command reports following error after registering the Oracle Linux 7/8/9 managed instance with OS Management Hub (OSMH) M…
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OSMH: How to Assign/Update New profile to Existing OSMH Managed Instance?APPLIES TO OSMH On-Prem GOAL How to Assign/Update New Profile to Existing OS Management Hub (OSMH) Managed Instance for which the profile is deleted or required an updat…
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OCI : Ubuntu instance is not accessible as router IP doesn't persist after rebootApplies TO: Oracle Cloud Infrastructure Linux OS SYMPTOMS Unable to access the ubuntu 22.04 instance as it loses router IP provided by DHCP for every reboot CAUSE Ubuntu…
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Linux: Executing ssh –X Gives error “/ usr/bin/xauth: error in locking authority file” for UserApplies to: Oracle Cloud Infrastructure Linux x86-64 Symptoms Connecting with ssh -X to a destination server results in a successful login but an error is displayed: /us…
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Problem switching from networkd to NetworkManager on Ubuntu 22.04On an Ubuntu 22.04 instance on Google Cloud, switching from networkd to NetworkManager is easy: $ sudo apt install network-manager $ sudo nano /etc/netplan/50-cloud-init…
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OCI : SSH Login Failed Due To Protocol MismatchApplies To: Oracle Cloud Infrastructure Oracle Linux - Version 6 Symptoms User is not able to login using private key with the following scenarios: Connection using “ssh…
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Oracle Linux – Fix KSPLICE was unable to install updates because a modified kernel is runningAPPLIES TO: Linux OS – Version Oracle Linux 7.0 to Oracle Linux 9.0 [Release OL7 to OL9] Linux x86_64 on Oracle Public Cloud GOAL: Install latest Ksplice patches. Sympto…Alejandro Rodriguez L.-Oracle 323 views 0 comments 0 points Started by Alejandro Rodriguez L.-Oracle Linux -
CUPS Fails to Print and Reports “Unable to get printer status”Applies to: Oracle Cloud Infrastructure Symptoms: After configuring a new printer in CUPS, the “lpstat” command shows “Connected to printer” but, after trying to print, …
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Linux: How To Extend a ROOT(/) Filesystem that is on a Logical Volume Manager (LVM) VolumeThis article describes how to extend the root filesystem "/" on Oracle Linux when it is located on an LVM volume. This procedure may be necessary if the root filesystem … -
SUDO Error "sudo: /usr/bin/sudo must be owned by uid 0 and have the setuid bit set"After connecting to the instance as an opc user, when you try sudo to root user, the following error is seen: [opc@ ~]$ sudo su - sudo: /usr/bin/sudo must be owned by ui…
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OCI: Yum Reports Error "Could not resolve host: yum$ociregion.$ocidomain; Unknown error"When trying to install packages on an Oracle Cloud Instance running a custom Oracle Linux image, yum fails with the following error: # yum -y install net-snmp Loaded plu…
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SSH Fails With Error: "FIPS mode initialized FIPS mode initialized ssh: connect to host <host name>SSH connections to an Oracle Linux 7 or higher fail, with the following errors logged to /var/log/secure: Oct 28 09:44:40 sshd: FIPS mode initialized Oct 28 09:44:40 s…
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Postfix Mail Server "/var/spool/postfix/maildrop" Mail Queue Fills /var on Linux InstanceA Linux instance is running the Postfix mail server. The /var/ filesystem on the server has filled to 100% utilization, and further checking subdirectories in /var shows…
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OCI: UFW Was Enabled on Ubuntu and SSH Connections Started to Fail With Connection Refused ErrorAn Ubuntu Instance started to experience "Connection Refused" errors when trying to log in to the server using ssh. This issue only started to occur after the Uncomplica…
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OCI: Linux User Account Incorrectly Set to "nologin"A local user account on a Linux instance was configured to use the nologin shell in error, as the user account needs to be able to log in to the Linux instance. Attempti…
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Unable to Remove LVM Snapshot - “Logical volume XYZ contains a filesystem in use."Attempting to remove an LVM snapshot on a linux instance fails with the following error: # lvremove /dev/VGExaDb/LVDbVar1Snap Logical volume VGExaDb/LVDbVar1Snap contain…
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OCI: Oracle Linux [UEK-5] Panicks With: "BUG: Bad page state in process lvm pfn:cbea9d1"Applies To: Oracle Linux - Version 7 or later with UEK5 Symptoms: UEK5 can suffer from memory corruption panic. [229802.917409] loop: module loaded [229803.641151] BUG: …
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System crash with: NMI received for unknown reason XX on CPU YApplies to: Oracle Linux - Version 7 and later Symptoms System crashed Crash report: [ 5629.913381] Uhhuh. NMI received for unknown reason 10 on CPU 5. [ 5629.913382] Do…
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OCI: aide(1) is Failing with FIPSR ErrorApplies To: Linux OS – Version Oracle Linux 7.0 to Oracle Linux 9.0 [Release OL7 to OL9] Linux x86_64 on Oracle Public Cloud Symptoms: AIDE is an intrusion detection uti…Alejandro Rodriguez L.-Oracle 61 views 0 comments 0 points Started by Alejandro Rodriguez L.-Oracle Linux
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Filesystem on iSCSI Volume is Not Mounted During BootApplies To: Oracle Linux - Version 8 and later Symptoms: Some filesystems randomly fail to be mounted during boot. The filesystems belong to iSCSI block volumes. Log can…
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Security Related Posts on Oracle Linux BlogAnalysis of CVE-2025-4598: systemd-coredump FIPS 140-3 for the Linux Kernel Understanding Spectre v2 Mitigations on x86 Pillars of protection—A holistic view of enterpri…
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Networking Related Posts on Oracle Linux BlogARP Internals: an in-depth exploration of how ARP functions RoCEv2 Congestion Counters Explained Oracle Linux 9.2 receives IPv6 Ready Gold Logo and meets USGv6-r1 standa… -
Migration Related Posts on Oracle Linux BlogUpdate CentOS Linux for free Still on CentOS Linux 7? Easily switch to Oracle Linux, a stable RHEL-compatible alternative Surprising reasons why CentOS users feeling str…
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Memory Management Related Posts on Oracle Linux BlogThe NUMA Awareness of the Linux Scheduler Memory Correctable Error (CE) - Userspace Control soft-offline pages oomwatch - A Userspace Out of Memory Killer - OLED Memstat…
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Data Storage Related Posts on Oracle Linux BlogIntroduction to ASMLib v3 Using drop_caches probably won’t crash your system What’s new for NFS in Unbreakable Enterprise Kernel Release 8? Device Mapper Multipath, an I…
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System Performance Related Posts on Oracle Linux BlogDetecting and debugging zombie memcg issues Syswatch - OLED Syscall latency... and some uses of speculative execution Tune it Up: Improving Redis Performance for Ampere …
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Oracle Cloud Infrastructure Related Posts on Oracle Linux BlogKVM Nested Virtualization in Oracle Cloud Infrastructure: A Hands-on Guide with Virtual Machines and Oracle Linux 9.5 Using Leapp to Upgrade Systems Managed by OS Manage…