Categories
poem

centos查找安装包信息

which mvn
rpm -qf /usr/bin/mvn
yum provides  maven
Categories
virtualization

备份术语

RTO(Recovery Time Objective)

一种业务切换策略,是容灾切换时间最短的策略。以恢复时间点为目标,确保容灾机能够快速接管业务。

RPO(Recovery Point Objective)

一种业务切换策略,是数据丢失最少的容灾切换策略。以数据恢复点为目标,确保容灾切换所使用的数据为最新的备份数据。

备份窗口

对数据进行备份而不严重影响使用该数据的应用程序时,进行数据备份的时间间隔。

Categories
vmware

vmware虚拟机打开电源慢的排查思路

文章来源:Solved: Problems with slow Power-on

  1. Run esxtop on the host where you start it up and look for high ready times on cpu, disk latencies for storage, or memory limits. Or check these values on the performance tab in vCenter – I prefer esxtop – it samples 4x as often by default and you can adjust the sample rate. Check vm properties in vClient as well as .vmx to make sure you do not have any limits set for this vm.

  2. Are these hosts all part of the same cluster?

  3. Do you use resource pools?

  4. Have you checked the logs on your host (var/log/… vmkernel, vmkwarning, as well as the vmware.log in the vm directory) ?

  5. What about the VM’s swap file? If the creation of that is slow, then the VM may take a long time to boot as well. Check to see where that is stored.

  6. Compare all of this VM’s settings to another VM that is not experiencing the problem.

  7. Does this happen with only 1 VM, a specific group of VM’s, or all of them? Does the slow boot vary across different VM types (cpus, memory, storage location, OS)?

  8. How many disks does this VM have? To power on the VM, the host has to write a lock entry on each lun the VM has disks on. Normally this takes a (1-2) MS, but if there is contention for lun meta updates (VMotions, VM power on, VM creation, snapshots growing) then this could delay the boot as well.

  9. What is the VM hardware version?

  10. VMTools up to date?
  11. Does the HAL match # of CPU’s?