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cron Error: bad username; while reading /etc/cron.d file on Linux

I am getting the following error in my cron job log file /var/log/cron.log:
       Aug 22 01:59:01 server2 cron[7510]: Error: bad username; while reading /etc/cron.d/backups
I have job entry as follows to run a job at 00:50 every day for root user:
       50 0 * * * /etc/cron.d/backups
How do I fix this problem on Linux or Unix-like system?
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How to make disk image with dd on Linux or Unix

How do I create disk image using dd command? How do I perform disk cloning from a live Linux cd for backup or recovery purpose?
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How to configure a static IP address on CentOS 7 / RHEL 7

I am a new sysadmin and CentOS user. My system is configured to use DHCP. How can I switch from DHCP to static IP address configuration in a CentOS 7 desktop system? How do I setup a static TCP/IP address on my CentOS Linux 7 or Red Hat Enterprise Linux 7 server using command line option?
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How to see PCI devices info on CentOS 7 and RedHat Enterprise Linux 7

I wanted to see PCI devices information on my CentOS/RHEL 7 box. But, I’m getting an error that read as, “-bash: lspci: command not found”. How do I solve this problem and see PCI devices information on CentOS/RHEL 7?
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How to see CPU temperature on CentOS 7 and RedHat Enterprise Linux 7

I am a new sysadmin of CentOS 7 server. How do I get my CPU temperature Information on CentOS Linux 7 or Red Hat Enterprise Linux 7 server?
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Linux how long a process has been running?

I‘m a new Linux system user. How do I check how long a process or pid has been running on my Ubuntu Linux server?
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How to determine Linux guest VM virtualization technology

I have a cloud-based virtual machine running Ubuntu and CentOS Linux server. It may or may not be virtualized. How do I determine what kind of virtualization technology (VMWARE/ KVM/ XEN/ VirtualBox/ Container/ lxc/Hyper-V etc.) a Linux guest system running on? How do I find out the virtualization type of a CentOS 7 Linux VPS?
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Linux Iptables Delete postrouting Rule Command

I am a new Linux server sysadmin. I need to delete POSTROUTING rule. How do I delete postrouting rule on Linux server?
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How to gzip and keep original file on Unix or Linux command line

I would like to compress a log file using gzip Unix command line utility, and I would also like to keep the original file. However, when I use the gzip my-app.log command, results in modifying my log file and renaming it my-app.log.gz. How do I force the gzip command to keep original file while maintaining the original file on Linux or Unix-like system?
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KVM libvirt assign static guest IP addresses using DHCP on the virtual machine

I am using KVM/libvirt on Linux operating system and how do I assign static IP address using dnsmasq dhcpd server for my default virtual network switch?
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