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The Journal Of A Linux Sysadmin

Converting between image formats

qemu-img convert: raw, qcow2, qed, vdi, vmdk, vhd The qemu-img convert command can do conversion between multiple formats, including qcow2, qed, raw, vdi, vhd, and vmdk. Image formatArgument to qemu-imgQCOW2 (KVM, Xen)qcow2QED (KVM)qedrawrawVDI (VirtualBox)vdiVHD (Hyper-V)vpcVMDK (VMware)vmdk This example will convert a raw image file named image.img to a qcow2 image file. $ qemu-img convert -f raw -O qcow2 image.img image.qcow2…

Unable to start MySQL on Ubuntu: AVC apparmor=”DENIED” operation=”open”

MySQL on Ubuntu fails to start. The following error messages are shown in the output of the journalctl -xecommand: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/666999/status" pid=666999 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=124 ouid=124AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=666999 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=124 ouid=0audit: type=1400 audit(): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/666999/status" pid=666999 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=124…

Ubuntu updates for TCP SACK Panic vulnerabilities

14.04 , 16.04 , 18.04 , ESM , Extended Security Maintenance , livepatch , sack panic , Security , TCP Sack Panic , Trusty Tahr Issues have been identified in the way the Linux kernel’s TCP implementation processes Selective Acknowledgement (SACK) options and handles low Maximum Segment Size (MSS) values. These TCP SACK Panic vulnerabilities could expose servers to a denial of service attack, so it is crucial…