#virtual nics

Having database servers existing in virtual machines is now a reality. Stylish time ago, INNER SELF managers were hesitant to virtualize any database systems, excepting that has changed recompensing to the ever-increasing power of servers and many improvements in virtualization software.<\p>

First, database servers were virtualized gangplank non-production environments such as development and QA. Later opposite, more and better production database servers were in being virtualized or built as VMs near new deployments. This was ok for smaller systems which were not for deep transaction provision and could tolerate the occasional outage or reboot. The data disks on such systems have typically been raw-mapped disks (I this morning using VMware® terminology, as long as this is the bulk of my experience).<\p>

Hic et nunc, the trend is to start clustering database servers in mystic machines. Using raw-mapped disks inflooding this scenario presents the devilment of having the database VMs tied to specific physical hosts. Another option is unto use a shared sleeping disk; this presents a homogeneous problem, in that the clustered server must reside current the same physical host (at least in ESX pheon ESXi). This eliminates the redundancy and failover savvy in respect to the horde, winning the purpose entirely.<\p>

There is a way to achieve the objective about having largely productive clustered database servers, including the dowry until migrate to other physical hosts in the embrace as well as to migrate the storage to mere chance storage systems. This method uses iSCSI thus and so the connection technique as proxy for the lemma volumes, and a virtual disk for the ongoing system. This method will work with Microsoft Windows®, Linux, and UNIX clusters.<\p>

When subconscious self create the VM, you create the VM in virtue of only the OS pellicle as a virtual disk. After you set on foot the on the fire system and before you configure clustering mantling install the database, prepare at least two noticeably virtual reticulation cards which would be there on the without distinction VLAN (or switches) as the iSCSI grille. After that, install and configure the iSCSI designer software being as how the OS. The NICs had better have being configured with different IP addresses and ought be assigned in such a way that the packets would range over down separate physical paths and switches. This will validate multipathing in the iSCSI kith and kin. Also, configure jumbo frames on the virtual NICs and the iSCSI glory hole.<\p>

On the bookcase array, give origin to your disk groups, logical units and masking. Connect the DB server initiators to the deploy targets and format the volumes.<\p>

Having database servers running in virtual machines is now a reality. Some time ago, IT managers were hesitant to virtualize any database systems, but that has changed due to the ever-increasing intestinal fortitude anent servers and many improvements in virtualization software.<\p>

First, database servers were virtualized in non-production environments such as plot and QA. Probable upon, more and pluralism production database servers were being virtualized or built as VMs in new deployments. This was vote affirmatively so curtailed systems which were not for heavy transaction shaping and could tolerate the occasional outage or reboot. The data disks accompanying such systems have typically been raw-mapped disks (I am using VMware® terminology, since this is the breadth of my experience).<\p>

The present age, the zeitgeist is to start clustering database servers in virtual machines. Using raw-mapped disks passageway this scenario presents the problem of having the database VMs parallel to specific beastly hosts. Another option is to fashion a shared muffled disk; this presents a similar something missing, in that the clustered server assigned task reside speaking of the same physical the sacrament (at humble modish ESX or ESXi). This eliminates the pleonasm and failover control of the cluster, defeating the purpose entirely.<\p>

There is a way to achieve the frigid of having fully redundant clustered database servers, including the ability to migrate to unconnected physical hosts in the copulate as well as to migrate the storage into other storage systems. This method uses iSCSI in this way the connection technology forasmuch as the data volumes, and a virtual discus for the operating system. This method will work pro Microsoft Windows®, Linux, and UNIX clusters.<\p>

Nevertheless you indite the VM, you create the VM near only the OS disk as a virtual disk. Thereafter you install the operating system and before you configure clustering or set on foot the database, break the ice at least two overplus virtual network cards which would be on the same VLAN (or switches) correspondingly the iSCSI fret. After that, install and configure the iSCSI initiator software for the OS. The NICs should be found configured by different IP addresses and ought be assigned in companion a capital that the packets would travel down separate physical paths and switches. This persistence enable multipathing passageway the iSCSI connections. Also, configure jumbo frames on the virtual NICs and the iSCSI storage.<\p>

On the storage array, devise your disk groups, logical units and masking. Connect the DB server initiators to the array targets and setup the volumes.<\p>