Intro to Xen-AoE
Home of the Xen-AoE cluster architecture
What is Xen-AoE?
Xen-AoE is a cluster server architecture which provides more efficient use of cpu, disk, and memory resources than traditional servers while providing zero single points of failure ensuring high availability and greater server maintainability. It does this by utilizing:
- CPU virtualization
- Storage virtualization
- SAN technologies
- Decoupling of disk
from cpu
- Commodity 64 bit x86 CPUs
- Commodity disk storage
- Gigabit ethernet infrastructure
Xen-AoE can save your business money by better utilizing hardware resources, simplifying management, and decreasing losses due to downtime.
What is Xen?
Xen is virtualization software made by Citrix/Xensource. It is similar to KVM, Qemu, or VMware. It allows us to run multiple servers/operating systems all inside one physical piece of hardware while providing isolation between them. From the Xen homepage:
Xen is a unique open source technology invented by a team led by Ian Pratt at the University of Cambridge and developed cooperatively by the world’s best engineers at over 20 of the most innovative datacenter solution vendors. With Xen server virtualization solutions, a thin software layer (known as the Xen hypervisor) is installed directly on the hardware, or bare metal, and is thereby inserted between the server’s hardware and the operating system. This provides an abstraction layer that allows each physical server to run one or more virtual servers, effectively decoupling the operating system and its applications from the underlying physical server. Xen’s paravirtualization technology is widely acknowledged as the fastest and most secure virtualization software in the industry and is enhanced by taking full advantage of the latest Intel® VT and AMD-V™ hardware virtualization assist capabilities. The Xen hypervisor is exceptionally lean-–less than 50,000 lines of code-–which translates to extremely low overhead and near-native performance for guests.
What is AoE?
AoE is a SAN technology invented by Coraid. Similar to Fibrechannel (but far less expensive) or iSCSI (but far simpler and more efficient). It is an open standard protocol which can turn any ethernet connected network of servers into a SAN. From the Coraid homepage:
ATA-over-Ethernet (AoE) is a simple block storage protocol that uses Ethernet to transport ATA disk commands, without burdening the packets with TCP/IP overhead. AoE is a robust network protocol designed to work on a lossy Ethernet network. Therefore the protocol must handle packet loss and packet errors without affecting the payload data integrity.
