Build a Cheap iSCSI SAN for ESX Server .
Companies producing storage subsystems for three years now repeat directly connected storage systems (DAS) is not enough flexibility, they create bottlenecks, and at the same time, the time required to administer them fairly large. The future of networked storage systems, which will have a repository anywhere on your network. And iSCSI technology is precisely designed to move storage to a new level. But if iSCSI is so beneficial, why we do not see widespread use? The fact is that except for very expensive infrastructure Fibre Channel, which is required for high-speed solutions, there is also a technical barrier. To understand the reasons for such slow spread of iSCSI, should consider in detail the protocol itself and its evolution.
The iSCSI protocol provides for the encapsulation of data in the IP-packets, which allows transmitting information on existing networks in the same way as in the case of an ordinary locally-attached storage device, such as UltraSCSI. Because of the wide variety of networks, IP (PAN, WLAN, LAN via Ethernet or Fibre Channel, WAN, MAN and LAN), storage area network (storage area network, SAN) based on the iSCSI protocol can easily overcome any distance because it is limited only performance networks used.
With this in mind it is understandable that the SAN is usually not extending beyond the limits of fast networks, which gives the mentioned technical barriers. Memory serving many customers should have the necessary bandwidth for this. Ethernet network at 100 Mbps, for example, could easily cope with iSCSI technically, but her performance is too little. Fibre Channel, by contrast, is too expensive technology for small and medium businesses.
The rapid development of Gigabit Ethernet, in fact, creates the foundation for applications iSCSI. While the most powerful and advanced gigabit network using optical, Gigabit Ethernet over copper will accelerate the transition from direct attached storage to network storage. This infrastructure is backward compatible, and pleasantly pleased its price. iSCSI stands for Internet SCSI, with SCSI, in turn, stands for Small Computer System Interface "(small computer system interface), towering over the other storage interfaces DAS in the professional field.
Connectivity:
The concept of iSCSI has arisen due to the fact that the interfaces such as ATA or SCSI limited to one computer and a maximum length of cable. So the flexibility of business applications, as well as corporate-level tasks is very limited. Ideally, the storage subsystem is better to withdraw from specific servers, to increase flexibility and to avoid bottlenecks. As a result, administrators can add, move, backup, restore and reconfigure the storage system without reference to any servers. And the use of existing network infrastructure for such stores - even a very good idea.
Of course, you can spend several hundred dollars on a SCSI cable or, worse, a lot of money on cables and accessories Fibre Channel. Today, Fibre Channel has become the main interface for professional applications and SAN because of the high bandwidth and large working distance. Indeed, the Fibre Channel connection can extend up to 30 meters in length using twisted copper pairs or up to 10 km during the transition to fiber-optic cable and transmission rate can be 2 Gbps or 4 Gbps. So the Fibre Channel network is quite capable to connect several buildings, while ensuring a very high speed and performance.
In addition, Fibre Channel can connect two devices on a point-point, used in conjunction with switches or work in controlled topologies resembling Token Ring. Finally, the technology is successfully coping with cells (cell) ATM, IP packet or SCSI, using their own frames (they are not compatible with Ethernet). For these reasons, Fibre Channel, and is dominated by the corporate sector.
But the components of Fibre Channel makes sense to buy only high-end environments: data or large databases. Infrastructure can be used as an interface between the hard drives and controllers, or to connect systems and storage units within the SAN (or both at once). However, if your corporate environment does not require extreme speeds, the additional spending meaningless. Why not, then select the Hardware Serial ATA, as well as the infrastructure is not dwell on the Gigabit Ethernet.
Storage
Today, professional storage system developed in the same direction as the printer a few years ago. We used to connect the printer directly to the computer through the parallel port interface or USB. In a corporate environment, printers located in the most convenient places. For example, next to the groups of workers, who often printed, or next to a computer made available for printing.
Then, when there were printers with network interface (same interface with the HP LaserJet JetDirect), made possible a more flexible arrangement and management. And printers have become independent of the computer. Storage systems are moving in the same direction. Today, if a user starts to miss the space, he adds hard drives. However, there were problems with the location and the stored data, available capacity or situations related to the file server downtime.
Indeed, today even small businesses should consider switching from file servers to networked storage (NAS) or flexible storage within a storage area network (SAN). Such networking solutions increase flexibility, scalability, availability. Increase and the possibility of redundancy and the physical location of the server no longer plays a role.
OpenFiler
Openfiler is an operating system based on CentOS and rPath x86 machines designed to convert into a complete NAS or SAN can handle up to 60 TB of data via the web interface you can easily create and manage the functions of storage, using 3 protocols such as NFS, SMB / CIFS, WebDAV, HTTP / 1.1, FTP and iSCSI. Openfiler can be integrated into existing networks using authentication mechanisms such as LDAP, Active Directory, NIS and Hesiod. It 'can also configure various RAID levels (0, 1, 5, 6 and 10).
With Openfiler is an easy-to-use operating system for a file server based on open-source base. Openfiler is a basis for rPath Linux and the installation is more than 15 minutes to be not. The system can be administered via a web user interface. Openfiler supports a variety of popular protocols to store data in the network, for example, CIFS / SMB, NFSv3 and NFSv4, FTP, and WebDAV.
Openfiler 2.3 is presented with a new surface. But even in the non-viewable areas has done a lot. So the system now supports multiple devices for network connectivity and the latest controller from 3ware, Areca, Adaptec and LSI. The Home-shares can be managed using network ACLs and keep the quotas due to new filters better view. iSCSIs (Internet Small Computer System Interface) can manage not only pleasant, but also their capacity to adapt dynamically. FTP and rsync settings can be made from now on a global scale.The easy option is using a open source storage management operating system called as Open Filer. If you want to virtualize correctly, you come to a SAN around, because all the virtualization methods that work with more than one host need a common block backend for data storage, if you called live migration (or VMotion, VMware wants to use).
I had an older server (dual-CPU, 2.4GHz, 2GB RAM, ICP RAID controller, 10 plates, 2xIntel-Gbit NIC) 'left', which I wanted to repurpose the iSCSI target. Earlier I had played once before with IET, the iSCSI Enterprise Target and its counterpart, the open-iSCSI initiator, therefore knows that it is and that the performance is adequate, but I did not feel like the whole lot again manually do so had to produce something finished.
Openfiler is the only known to me ready and cost-neutral solution that provides iSCSI, so the choice was not difficult. Openfiler is an rPath Linux-based NAS / SAN appliance that not only iSCSI, but also other protocols speaks (NFS, SMB / CIFS, FTP, HTTP / WebDAV, etc.)
Installation is quick of hand, negative, I only notice that there is no sensible automatic partition method, but you have to manually create the three partitions (/ boot, swap and /) according to the instructions. If you use this method to automatically partition you have a huge partition for /, but nothing left for the actual task, namely to serve as a filer.
Openfiler Setup:
OpenFiler is an open source NAS that can be installed on a computer no longer used to recover a bit hardware. Just a PC, a small hard drive to install the operating system and one or more large hard drives for use as archival. Installing OpenFiler is very simple. Just download the ISO file from the manufacturer's website , burn it and start the PC boot directly from CD-ROM. The procedure is very similar to those of all other Linux systems currently online. It 'can choose to perform an installation in a chart or in text mode (especially for computer dating or who does not like the graphical interface).
Will be asked the usual things like language, area, disk partitioning (an automated process cannot go nuts with partitions, a procedure manual is available for advanced users), network adapter settings and password for the root user.
After installing just restart your computer (without the CD-ROM) and a text interface will show us that the system is ready to listen and to be administered via the web at https: / / xxx.xxx.xxx . XXX: 446 (instead of xxx enter the IP address of your network card already configured).
From any network location so you can open your favorite browser at that address, accept any notices warning of the connection of insecurity due to the fact that the encrypted connection was made without a certificate generated by certain entities, and you will go to page login. To enter the site configuration openfiler NAS type user name and password as the word password (which can later be changed by the user).
At this point it is necessary to configure the NAS Server. This procedure is suitable for consumers with extensive expert. The manufacturer's site, in addition to the FAQ and documentation, there is also a forum where you can find answers to common configuration problems. For people who need specialized technical assistance is available to buy support packages or manuals directly from the manufacturer.
Steps :
•After installing Openfiler and rebooted, we can connect via Web console for remote administration system.
•Then type in the address bar of your browser: https: / /
•Default user for the administration is openfiler with password
•You will end up in the GUI to admin status page
•From this page you control the hardware monitoring system, its uptime, its average load, etc. .., and access to other configuration pages.
•On this page you can configure system settings such as IP address, networks or VLANs that may have access to storage, set a high-availability/replication partners which replicate data for redundancy, set the clock system, drive a UPS, upgrade and have an access to a shell ssh.
•On this page you can create storage volumes, each with a file system and a possible RAID configuration.
•OpenFiler uses the Linux Logical Volume Manager (LVM ) As a volume manage and supports both ext3, xfs and iscsi. In my particular case I created an entire book that I added later as iscsi storage to my VMware ESX server. Follow a short post on how to add volumes created by openfiler on VMware ESX.
•The next tab is the fee that allows you to precisely set the quota for each volume created, for example if openfiler is used in a corporate environment with different departments within you can allocate a quota of 2GB each user group marketing and differently for each user group's engineering to allocate a quota of 10GB.
•By the share manager can create subdirectories by assigning specific volumes of different network services to share.
•Example: The marketing department essentially uses the Windows client and then their shared network folder is by using only the service openfiler SMB / CIFS, but the department engineering using Linux and Mac clients, so their resources will be shared with Services SMB / CIFS and NFS.
•This example highlights the flexibility, ease of use and power of the excellent Openfiler.
•From the home page of the service manager can enable or disable network services offered by openfiler, for example if you use only as Openfiler NFS server can turn off other services such as SMB / CIFS to save memory to the system.
•You can enable Openfiler to be a target server for iSCSI connections, configure the service to drive a UPS, and then shutdown the system in case of power failure or enable LDAP authentication of the service users, etc.
•Finally there is the account manager that allows you to define the type of authentication.
•You can use Openfiler as LDAP server where users and groups are defined locally, or you can Openfiler can point to an external LDAP server or NT Active Directory to authenticate users / groups.
•One of the most interesting Openfiler is the ability to create a Distributed Replicated Block Device (DRBD) with another Openfiler in a synchronous or asynchronous data backup and High Availability (HA), creating a fault-tolerant data-storage cluster.
Some Conclusion for Openfiler :
•Anticlimax after the reboot: The standard 2.6.19 kernel with smears from 32-bit SMP systems and does not even boot. The problem has been known for a long time, but was not resolved, although it would be easy to create a new Install-CD.
•I get the indication that a uniprocessor kernel in the system you may easily customize the GRUB is the path, and the system also starts.
•Openfiler is administered via a semi-compliant web front end, although the total and forth in the volume management seems a little chaotic to.
•The update of the system can also be done via the interface, but I use the other method a direct SSH login. This is then updated the kernel (the new SMP solves the problem but not too) and then immediately turns off iscsi_trgt.
•If you install this again, will turn one another, not so recent kernels installed, which is present at least once as a non-SMP version.
•Here I also collect first experiences with Conary, the package management of rPath.
SCSI
The hardware used by VMware iSCSI initiator support physical iSCSI host bus adapter (HBA), Qlogic QLA4050 iSCSI HBA e.g. An iSCSI HBA connects to the SAN via Ethernet and TCP / IP network ready. The hardware initiator does not appear in the network configuration of the ESX hosts. Instead, he appears as a storage adapter in the storage configuration.
Functions of the hardware iSCSI initiator :
•ESX Server Boot from iSCSI SAN is only possible with the iSCSI initiator Hardware.
•Multipathing support for failover, but no load balancing
•Support for VMotion, VMware HA and VMware DRS
The configuration of the software iSCSI initiator in VMware ESX requires a VMkernel port and a service console port. Both must be on the same subnet. With ESXi is only one VMkernel port is necessary. The correct configuration of the VMkernel port can be the medium vmkping be reviewed command. When multipathing is defined as the use of multiple independent physical links (paths) between host and storage system. If an active path fails then an alternative path is utilized to connect to maintain. Such a process is called path failover (Failover Path). VMware ESX does not currently support Microsoft MPIO or Multiple Connections per Session. However, there are two options to use multipathing mechanisms.
And the iSCSI connoisseur will immediately recognize this a first error: _ are not allowed in IQNs, however, did not catch the Openfiler, so that one is here only once before the wall. Interestingly, Open-iSCSI is not interested in Linux for it, while Microsoft initiators with a (misleading) error message, but quite rightly, complained.
Discovery with SendTargets was no problem, but after logging onto the target nothing happens. No new record, not a block device, only the terse message that there are now scsi2 host adapter.
Openfiler is an operating system dedicated to network storage, equipped with a management interface accessible via the web. Offers comprehensive storage capabilities, and NAS (Network Attached Storage) and SAN (Storage Area Network) into a single integrated framework. Openfiler uses any standard x86 servers (both 32 and 64 bit) and converts it into a powerful network storage appliance capable of providing cross-platform compatibility in heterogeneous network environments by supporting the most popular storage protocols (e.g. CIFS and NFS), and providing support for Windows, Linux and Unix.
SAN Melody Lite -
SANmelody is software that turns a Windows server platform as a true virtualized storage. In fact, installing SANmelody access services in standard mode SAN iSCSI (Internet Small Computer Systems Interface) or Fibre Channel. Remember iSCSI is a standard for interoperability between different storage systems that otherwise would not be compatible. SANmelody configuration requires a basic entry-level to work. It installs on a server running Windows 2000, XP or Server 2003 with a network interface and including at least 512 MB of RAM. It does not work with 64-bit versions of these operating systems. The software does not differentiate the type of disc used for storage that can be SCSI or Sata.
We can thus implement a storage server comprising inexpensive SATA disks. This is one of the advantages of this solution, the other being the ability to install configurations on older or entry level. For optimal operation of the server, Datacore recommends not to use the disk's boot Windows as storage media. SANmelody Lite is dedicated to small businesses, workgroups and intensive user environments with three or more PCs that need extra disk capacity or move the disk from one system to another. This software uses the iSCSI protocol to allow Windows machines, Apple and UNIX / Linux lack of ability to access additional disk space over a LAN, just like other drives were installed internally, but slow performance, compatibility issues or complexity often associated with network shares.
The skills needed to implement SANmelody are minimized, which makes it perfect for small structures. Recall that for SOHO and telecommuters, a variation called SANmelody Lite is available. It is also possible to test a trial version of the software for 30 days. Moreover, it took us less than half an hour to install and implement SANmelody server. In addition to the documentation, including a step-by-step explanation of the installation, we particularly liked its ease of administration. Indeed, the software uses the MMC interface (Microsoft Management Console) to which it integrates.
Once installed, it only remains to allocate the storage space and this is where virtualization. Indeed, resources are shared regardless of physical location. It allocates partitions to servers that are configured to turn back on the score (which actually looks like a volume) that is assigned to them. For storage software solution, SANmelody shown good performance during backups. There is no latency and cache management can be configured to speed up transfers. SANmelody is an excellent alternative to acquiring a dedicated storage array and a great way to recycle older servers with storage servers by adding a few record
SANmelody Lite offers the following advantages:
•It is an inexpensive software that offers the key benefits of SANs, the cost of extra hardware and less.
•It requires only basic Windows skills, he moved easily and quickly.
•It allocates disk or a part of the space of disk drives optimally to each computer over the network.
•SANmelody Lite allows companies to accomplish more tasks over a given period. It utilizes the PC resources to improve the performance of tasks requesting more disks.
•It supports IPSec encryption to secure transactions and manages the audit Mon-client to allow the disk servers to allocate disk space safely, without compromising the confidentiality of data.
•It runs on PCs with Intel and AMD standard Ethernet and Gig-E and all storage devices supported Windows disk (IDE, SCSI, FC, SATA).
•It improves disk management and turns it into service across the network coexist with other Windows services, such as file sharing and printing, with minimal impact.
SANmelody is on the market longer than Open-E iSCSI, and is more powerful solution iSCSI. However, to implement SANmelody need a fully functional server, including the system hard drive and a license for the operating system. In addition, prices for SANmelody comes with $ 1178, which is approximately two times higher than the Open-E iSCSI Enterprise edition. In addition, $ 864 to spend on upgrading, which will provide options to create images and automatic initialization (it will allocate the available capacity dynamically). Nice features. But for supporting multi-terabyte arrays and multiple processors will have to pay more.
Conclusion
Except for the entry-level version, SANmelody supports Fibre Channel and offers a number of functions to which the Open-E is still far: you can specify automatic processing failures (auto failover) and asynchronous replication IP (asynchronous IP replication), which allows you to automatically replicate data over the Internet that is always available to create a mirrored storage. Not a bad idea for applications that require maximum uptime. On the next page you can view a list of available versions. By the way, if SANmelody not be able to meet your needs, then pay attention to SANsymphony. This application is aimed at large-scale enterprises.
No comments:
Post a Comment