VMware Admin Questions and Answers
1. What is VMHA?
|HA provides High availability to the Virtual machine and application by migrating the Virtual machine from One ESX host to another ESX host and reboot in case of any host failure.|
2. What are pre-requites for HA to work?
|• Minimum of two ESXi hosts • Minimum of 3 GB memory per host to install ESXi and enable HA • VMware vCenter Server • Shared storage for virtual machines|
3. Port no for HA?
|2050 – 2250/UDP/VMware HA 8042 – 8045/TCP/VMware HA|
4. What is maximum number of primary HA hosts in vSphere 4.1?
|Maximum number of primary HA host is 5. VMware HA cluster chooses the first 5 hosts that joins the cluster as primary nodes and all others hosts are automatically selected as secondary nodes.|
5. What is new in VMHA?
|• Fault Domain Manager (FDM) is the new HA agent and replaced AAM (Automated Availability Manager) agent. • VMware HA is no more dependent on DNS. • No more Primary / secondary node mechanism has been completely removed and replaced by Master / Slave concept.. • Supports Management network partitions. • Data store Monitoring is the new feature in Sphere 5.|
6. How VMHA works?
|• In 5.0 HA works with Mater/Slave concept. One Master and other slave. • Once we enable HA in cluster level election process happens and prompt one host has master. • HA election takes place 15 seconds. • Master will be elected using the election process that the host has most number of datastore . If or more ESXI host has same number of datastore using MOID (managed object ID) master will be elected. • In VMHA 5.0 in a cluster we create maximum of 32 host.|
7. How to check the Master host in the cluster?
|Click cluster -> summary -> Cluster status|
8. Different types of heartbeats in Vsphere 5.0?
|There are 2 different types of heart beats Network Heartbeat Data store Heartbeat Network Heartbeat: • In Network Heartbeat each slave will send the heartbeat to master and master will send the heartbeat to slaves. • These heart beat take place every second. • Heartbeat will check up to 15 seconds still the slave is not receiving the heartbeat from Master; it will try to determine that the master is Isolated or Failed. Datastore heartbeat: • Datastore heartbeat is the new feature in Vsphere 5.0 • Using Datastore heartbeat only master will check the last update of the failed host(Check whether the host is accessing the datastore or not). In case the host can able to access the datastore it will determine has Isolated or else host was not able to contact the datastore, it will determine has Failed.|
9. What is Isolation and Network Partioned?
|Isolation : When the ESX host loses its ability to exchange heartbeat via management network between the other hosts in the HA cluster, that ESX host will be considered as a Isolated. Network Partioned: When the multiple host is isolated but can still communicate with each other over the management network its is called as Network partioned. Restart Priority: VM restart are prioritized in to different type Agent Virtual machine(Eg :Vshield ) FT secondary VM. Virtual machine with High priority Virtual machine with Medium priority Virtual Machine with Low priority.|
10. What are the benefits of virtualization?
|Virtualization is a creation of virtual machines and to manage them from one place. It allows the resources to be shared with large number of network resources. Virtualization is having lots of benefits and they are as follows: 1. It helps in saving lots of cost and allows to easily maintaining it, in less cost. 2. It allows multiple operating systems on one virtualization platform. 3. It removes the dependency of heavy hardware to run the application. 4. It provides consolidating servers that are used for crashing of a server purpose 5. It reduces the amount of space being taken by data centres and company data.|