Category: VMware

1. Hardware iSCSI Features and Limitations Below are some items to consider if you are planning to use the iSCSI hardware intitiator. ESX Server host booting from iSCSI SAN is possible only with hardware iSCSI initiator Multipathing support for failover only, no load-balancing by using multiple QLA4010s Support for VMotion, VMware HA, and VMware DRS Support for RDMs No support for Microsoft Cluster Server No VMware Consolidated Backup over iSCSI 2. Software iSCSI Features and Limitations Below are some items to consider if you are planning to use the iSCSI software intitiator. No support for booting ESX Server from software […]

A basic difference between iSCSI and Fibre Channel is that when an iSCSI path is overloaded, the TCP/IP protocol drops packets and requires them to be resent. Fibre Channel communications over a dedicated path are not at risk of being overloaded. When a network path carrying iSCSI storage traffic is oversubscribed, a bad situation quickly grows worse and performance further degrades as dropped packets must be resent. Another potential disadvantage with implementing software-initiator iSCSI (but not hardware-initiator iSCSI) is that standard 10/100 Ethernet interfaces do not have enough throughput for practical iSCSI work. Gigabit Ethernet interfaces are required, and those […]

HA stands for one of the critical enterprise cluster feature of VMware called “High Availability”. It can be configured on a VMware cluster to auto recover VM’s from a ESX host failure. When you configure HA via vCenter Server on VMware cluster, it installs Automated Availability Manager (AAM)  (VMware HA agent) on individual ESX host The HA agent (AAM) runs a heartbeat mechanism on each host in a cluster to signal that the host is running and is a part of the cluster. g gf