kernel panic at boot with error: Unable to mount root fs on unknown-block(0,0)
After you install or update CentOS/AlmaLinux on a server or a kernel update, the system may fail to boot with the following error. VFS: Cannot open root device XXX or unknown-block(0,0)Please append a correct "root=" boot option; here are the available partitions:Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)...Call Trace:[<ffffffff81527213>] …
Microsoft may block installing updates on a PC with older CPU
Microsoft has released Windows 11, and you may have decided to upgrade Windows 10 on your PC to Windows 11. Before you embark on this mission, note that Windows 11 is not supported on Intel 6th (Kabylake) and 7th (Sky Lake) generation Intel CPUs. Your PC must be equipped with an 8th generation Intel CPU …
How to search for text files in a directory and add .txt suffix to their filenames?
On the bash command line, run the following command to search for text files in a directory and add .txt suffix to their names. # for i in $(file * | grep ASCII | awk -F : {'print $1'} | xargs); do mv "$i" "$i.txt"; done
Find files which has SUID/SGID and disable the security bit?
To find files with SUID/SGID set and disable their security bit, you can use the Linux Find command. Under root, find all set user id files with the following command. # find / -perm +4000 Find all group id files under / # find / -perm +2000 You can combine both the above find commands …
How to change the LiteSpeed connection timeout?
If you see errors like the following you need to change the LiteSpeed connection timeout setting. 2021-09-01 03:33:04.222931 [INFO] [12071] [198.51.100.2:11313#APVH_domain.tld:lsapi] Lsapi connection state: 3, watching event: 25, respState: 1, m_iTotalPending:0, m_iPacketLeft:0, m_iCurRespHeader:12, req sent for 121 seconds,Total processing time: 121. Login to the cPanel server as root and access the LiteSpeed WebAdmin console. You …
How to update composer on cPanel server?
It is usually recommended to download Composer to a local user home directory and use a local version that skips workarounds as required by using a root-level version. Only root is able to update system-level Composer. Local users can update Composer only if they install Composer locally and are not using the root-level Composer provided …
Find and delete older files
In a Linux server, finding and deleting files older than 7 days can be done as follows. You should use the find command to get a list of files older than 7 days with the following command. # find /directory-path -mtime +7 -type f -exec ls {} ; In case, files you are looking for …
Disable and enable ceilometer in OpenStack
Stop telemetry on the overcloud controllers. systemctl stop openstack-aodh-evaluator openstack-aodh-listener openstack-aodh-notifier openstack-ceilometer-central openstack-ceilometer-collector openstack-ceilometer-notification openstack-gnocchi-metricd openstack-gnocchi-statsd Next stop the mongod service. systemctl stop mongod You should now backup MongoDB files. tar Jcf /tmp/mongodb-backup-$HOSTNAME-$(date +%F_%H%M%S).tar.xz /var/lib/mongodb Delete the content of /var/lib/mongodb folder as follows: rm -r /var/lib/mongodb/* Run mongodb on all controllers. systemctl start mongod Create …
Risks of leaving older kernels installed
Are you concerned when some security software flags older kernels as security threats due to known bugs and vulnerabilities? Does leave those outdated kernels installed on a server opens a door for malicious attacks? After upgrading the server or updating the Linux kernel, leaving old kernels installed likely does not open an attacking threat against …
can’t find command `multiboot2′ – TBOOT fails in UEFI system
In a UEFI system, after installing TBOOT, the TBOOT GRUB menu entries fail to boot the kernel. The following error message will be output on the screen. error: ../../grub-core/fs/fshelp.c:218:file`/EFI/centos/x86_64-efi/multiboot2.mod' not found.Loading tboot 1.10.2 ... error: ../../grub-core/script/function.c:120:can't find command `multiboot2'.Loading Linux 4.18.0-305.10.2.el8_4.x86_64 ...error: ../../grub-core/script/function.c:120:can't find command `module2'.Loading initial ramdisk ...error: ../../grub-core/script/function.c:120:can't find command `module2'. Press any …
TBOOT boot crash observed with TPM 2.0 in UEFI mode
When TPM2.0 device is in UEFI mode, booting the kernel through TBOOT hangs. The root cause of this error is because GRUB package included with Alam Linux 8.3 does not implement the complete stack to validate kernel command line parameters. To resolve this issue, upgrade the system to AlmaLinux 8.4/CentOS 8.4. If somehow you cannot …
What is Bitcoin? History & Technical details – Blockchain, Hash, Wallet & Investment
Introduction In January 2009, a decentralized digital currency called Bitcoin was created that allows users to buy, sell, and exchange its value without the use of a middleman, such as a bank. Unlike other online payment methods, Bitcoin is based on peer-to-peer software, protocols, cryptography, and the lowest transaction fees. The market capitalization of Bitcoin …
Cryptocurrency Mining Explained
What is Cryptocurrency mining Cryptocurrency mining or crypto mining uses computational power to generate new cryptocurrency units by solving complex mathematical problems or algorithms. The cyber currency transactions are verified, and the miners (like auditors) distributed globally are rewarded with a small percentage of cyber currency. e.g., Bitcoin, Etherium, BTC, Dogecoin, etc. Cryptomining can be …
How to distinguish between LHR and FHR nvidia graphic card?
After NVIDIA released their Ti range of consumer graphics cards, there were many misunderstandings regarding Lite Hash Rate (LHR) graphic card and Full Hash Rate (FHR). RTX 3060, RTX 3060 Ti, 3070 Ti, and 3080 Ti graphic cards are LHR since NVIDIA released them. It is important to note that RTX 3090 is an FHR …
