Having the following notification after adding a new VMFS volume to your VMware vSphere/vCenter 6? Deprecated VMFS volume(s) found on the host. Please consider upgrading volume(s) to the latest version. If this message show up even though they are at the latest version, it mean you have hit a known issue of vCenter 6 (which… Read More »
Having this error message trying to open a virtual machine (guest) console? The VMRC Console has Disconnected. Trying to reconnect This is probably because either your host or vCenter server does not have the necessary ports opened or filtered. You should have the following port opened on the firewall : tcp-443 tcp-902 tcp-7331 tcp-9443 (vCenter… Read More »
VMware ESXi hypervisor have some great SNMP capability, whatever to gather information status of your hardware, monitoring or statistic usage of your resources. Follow these easy steps to enable such feature. 1. Enable SSH from the vSphere client and connect to it using your favorite terminal application : Configuration tab > Security Profile > Services >… Read More »
Getting this output on your RHEL/CentOS virtual machine? Clocksource tsc unstable (delta = 000000000 ns). Enable clocksource failover by adding clocksource_failover kernel parameter. First find out the available clock sources : cat /sys/devices/system/clocksource/clocksource0/available_clocksource You will likely get the following results : kvm-clock tsc acpi_pm You are currently using “tsc” as per the initial output error, try… Read More »
I recently faced the following issue with VMware ESXi vSphere 5.5 hypervisor, trying to connect a USB device to a virtual machine. The host server was actually able to see the USB device : lsusb Bus 02 Device 04: ID 1058:0748 Western Digital Technologies, Inc. Bus 02 Device 03: ID 09eb:0131 IM Networks, Inc. Bus… Read More »
If after a power outage or ESX hypervisor shutdown your iSCSI datastores are missing, it might be caused by a lock on the LUN on your host machine. You may find this in your vmkernel logs : /var/log/vmkernel.log 2014-02-19T04:19:11.927Z cpu3:33477)NMP: nmp_ThrottleLogForDevice:2321: Cmd 0x88 (0x412e80814440, 0) to dev “t10.FreeBSD_iSCSI_Disk______74867ae04094000_________________” on path “vmhba37:C0:T1:L0” Failed: H:0x2 D:0x0 P:0x0 Possible… Read More »
It’s possible to tell the kernel of your Xen guest VM to synchronize or not the clock with the physical host machine. There are numerous reason why you would or not to use this feature (such as your guest VM is behind or forward the clock over time). To find out the current setting, simply… Read More »
VMware ESXi management IP/vSphere connectivity might become suddenly unavailable over the time or after replacing the network interface card. This can be easily resolved by removing the vmnic port groupe for the management network and add it back again to the vSwitch. You will need direct console access to the ESX shell to perform these… Read More »
Ending up with this kind of error booting a guest machine on your Xen hypervisor? Running: xm create /cloud/config/hjxmogr553e5jx Using config file “/cloud/config/hjxmogr553e5jx”. Error: Unable to connect to xend: No such file or directory. Is xend running? Fatal: Virtual machine has not been started on hypervisor Executing Rollback… The two possible causes would be the… Read More »
Oracle VirtualBox do not have such feature through the GUI. However, you can use the command line and the task scheduler to do so. First, you need to grab guest virtual machine ID that you want to be started in background. Open the command prompt, and change directory as followed : cd C:\Program Files\Oracle\VirtualBox\ Then… Read More »