9Feb/170

Advantages of ZFS

ZFS as a rather new filesystem offers various advantages in comparison to regular filesystems like ext3, ext4 and NTFS. We have summarized the most noticeable ones as follows:

The main benefit of using a ZFS filesystem is guaranteed data integrity

ZFS protects your data by enabling volume management on filesystem level. This feature makes “Copy on Write” (CoW) technology possible. When a block of data is altered, it will change its current location on the disk before the new write is finished. If your system crashes or loses power in the process, that data would be lost or damaged. ZFS does not change the location of the data until the write is completed and verified, thus keeping your data safe in case of a system crash. To verify data integrity, ZFS uses checksums to ensure that the data remains original from write to write. This means that every write is tested, which in turn eliminates bit rot. ZFS not only protects your data with the CoW feature, but offers additional RAID protection in comparison to standard RAID levels. RAID-Z3 allows for a maximum of three disk failures in a ZFS pool. Regular RAID only allows for two disk failures per volume. ZFS offers the ability to set up a multi-disk mirror (nRAID). Usually the RAID mirrors are composed of a single disk and its copy. With a multi-disk mirror you can have multiple copies, which adds levels of data integrity not found in typical RAID setups and is great for read speeds.

Highly Scalable

The storage capacity of ZFS is years ahead of what might become a problem soon for regular filesystems. The possible maximum of a ZFS storage pool is 6 EiB = 16 * 2^60 Byte, which is as much as 3,000,000 6TB HDDs. A configured ZFS pool can easily be changed in its size to accommodate a growing need for more storage. The pool can be upgraded step by step with larger disks, without compromising the filesystem or complicated procedures. Harddisks can even be added on different physical ports or in a changed order in a new computer system, as long as the ZFS version on the target system is the same or higher. You will be able to use your migrated data as soon as the import is completed.

Improved Performance

ZFS also allows to send writes to individual physical disks, instead of just the RAID volume. Because of this, ZFS can stripe writes across RAID volumes, which is speeding up write performance. In the case you need to sync mirrors with only a little bit of information, you do not have to wait for it to sync any of the empty disk space, which can take a good amount of time. ZFS incorporates algorithms to ensure that your most recently used and most frequently used data are kept in the fastest system storage media. Spinning disks are known to be slow and SSD drives come at a very high price compared to regular disks. By using these algorithms in combination with flash-based ZFS write cache and L2ARC read cache devices, you can speed up your performance by up to 20% at low cost. Other great feature of ZFS are the intelligently designed snapshot, clone, and replication functions. ZFS snapshots only update based on what has changed since the last snapshot. This means that clone and replication tasks are less time consuming compared to traditional replication technology.

Easy to administer

Creating a new ZFS-Pool is fairly simple. The available storage devices can be listed with “rmformat” and can be created with the “zpool create -m /mountpunkt Contabo1 DEVICE” command. The new filesystem is automatically mounted and immediately accessible. There is no need to format the new ZFS-Pool. If additional storage space is needed, you can easily add a new device with the “zpool add Contabo1 DEVICE” command. This compares to the classical RAID 0 in which the data is distributed on all available devices.
In general a setup for data integrity is much more adviseable. With the “zpool create Contabo1 mirror DEVICE DEVICE” command you can easily create a ZFS-Pool with mirrored disks as in comparison to a classical RAID 1. You can also add several mirror disks to enhance data integrity even more with the “zpool create Contabo1 raidz DEVICE DEVICE DEVICE DEVICE” command for example. This will create a ZFS-Pool with four disks, in which one is allowed to fail without issues. When using the raidz2 option instead of raidz, two disks can fail at a time.

There is also the option to add Hot-Spares to a ZFS-Pool in order to have a replacement disk ready at all times. If a live disk fails the Hot-Spare will be used automatically to start a rebuild and take the place of the failed disk. This can be done with the “zpool add Contabo1 spare DEVICE” command, which will add the last disk in our example to the pool as Hot-Spare.
With "zpool list" you can review all existing ZFS-Pools with size, usage and health status.
With “man zfs” and “man zpool” you can review the commands that will give you full control over your ZFS-Pools.

A short overview of the mostly used commands:

- Creating a RAID-Z pool
zpool create NAME raidz DEVICE DEVICE DEVICE
- Creating a mirrored pool
zpool create NAME mirror DEVICE DEVICE
- Listing of available pools
zpool list
- Show I/O for all pools
zpool iostat 1
- Show attributes of pool devices
zpool vdevs
- Add disk to a pool
zpool add NAME DEVICE
- Delete a pool
zpool destroy NAME
- Creating and mounting a ZFS-Pool
zfs create POOL/NAME
- List pool filesystems
zfs list
- Creating and mounting a ZFS-Pool on a non-default mountpoint
zfs create POOL/NAME /MOUNTPOINT
- Create a snapshot of a filesystem
zfs snapshot POOL/FILESYSTEM@SNAPSHOTNAME
- Mount a ZFS-Pool
zfs mount POOL/FILESYSTEM /MOUNTPOINT
- Delete a ZFS-Pool
zfs destroy POOL/NAME

Which operating systems are compatible with ZFS?

ZFS was initially designed for Solaris, but can be used today on FreeBSD, FreeNAS, Proxmox and most linux distributions.

Posted by: Philipp | Tagged as: , , , , , No Comments
15Jan/132

High demand for our VPS and Dedicated Servers!

Short after our company name change we reduced the prices of our dedicated and virtual servers and some of our upgrades.
Since last week our high-end server “Dedicated Server X”, which includes a powerful Intel Core i7 3930K processor, 64 GB DDR3-RAM and 256 GB SSD with 6 Gbit/s + 3 TB HDD, can already be ordered at the ridiculously low cost of 109.99 EUR/ month.
Have a look on our server overview at http://contabo.com/?show=servers – our prices of all other servers are quite reasonable as well.

Furthermore, we doubled the performance of our Virtual Private Servers (VPS). From now on, our customers get 16 GB RAM for only 29.99 EUR/ month. These 16 GB RAM are guaranteed to be available, contrary to other offers. You get 100% performance in full!
In addition to that the virtual machine offers 800 GB HDD and 4 cores with 3,2 Ghz each. All together for just 29.99 EUR/ month is a more than excellent cost-benefit ratio, in our opinion.

The consequences of the price reduction are not really very surprising for us but very pleasing. Every day our support team, that is responsible for new customers and for the setup of all ordered hosting products, is doing a great job by providing almost instant setup, usually within a few hours after receipt of payment.

When we checked our new orders today at 10.30 in the morning we already recorded new orders of
- 30 VPS and
- 4 Dedicated Servers.
We are already excited what count we are going to reach at the end of the day ;-).

Parallel to all the new orders the volume of support requests increases. Reasons for that are not because of errors or malfunctions of our server hardware – most of the support enquiries contain individual requests, technical issues and the startup procedure of the servers by the customers.
Even in times when more assistance is required by our customers we are taking care of every phone and email enquiry instantly, often only within a few minutes.
In short: Contabo is able to provide competent instant service and also care for individual requirements someone may have. The office is occupied from 8 am to 11 pm on 365 days a year including holidays and weekends.

We would like to take this opportunity to say thank you to all our new and existing customers. Thank you for having placed your trust in us! We promise to keep on working hard to provide optimum service in combination with an excellent price performance ratio.
For further questions or a detailed product advice feel free to contact our support team (support@contabo.com). We are looking forward to your request.

9Jan/138

Price reduction for all dedicated and virtual servers!

The journey has just begun!

This is probably the most appropriate description in one sentence for our ambitious plans for the year 2013.

A few weeks after changing our company name, we are innovating the market for dedicated and virtual servers.

Contabo reduces the prices of all dedicated and virtual servers (VPS) and doubles the VPS performance at the same time!

The self-conception of Contabo does not only imply top-level support that is second to none. Between 08:00 am and 11:00 pm, our support teams answers 99 % of all incoming emails within less than one hour or even within a few minutes in most cases.
Besides that, one of our main business objectives is to offer cost-effective products undercutting the prices of all our competitors.

Our principle - optimal performance at a minimum price - is implemented once more today. We proudly present:

The new Contabo dedicated and virtual servers at an unbeatable price.

1. Contabo dedicated servers - now even more attractive!

Dedicated Server Duo
Intel Core 2 Duo (2 x 2.13 GHz)
3 GB DDR-RAM
400 GB HDD
100 Mbps switch port
Unlimited Traffic
Only 59.99 EUR / month!
Setup-fee starting at 0 EUR depending on the contract period!

Dedicated Server Quad
Intel Core 2 Quad 4 x 2.4 GHz
8 GB DDR2-RAM
2 x 400 GB HDD
100 Mbps switch port
Unlimited Traffic
Only 69.99 EUR / month!
Setup-fee starting at 0 EUR depending on the contract period!

Dedicated Server Core i7
Intel Core i7 920 4 x 2.66 GHz
12 GB DDR3-RAM
2 x 1000 GB HDD
100 Mbps switch port
Unlimited Traffic
Only 79.99 EUR / month!
Setup-fee starting at 0 EUR depending on the contract period!

Dedicated Server 6-Core
Intel Core i7 980 6 x 3.20 GHz
24 GB DDR3-RAM
80 GB Intel Postville SSD
2000 GB S-ATA HDD
100 Mbps switch port
Unlimited Traffic
Only 89.99 EUR / month!
Setup-fee starting at 0 EUR depending on the contract period!

Dedicated Server X
Intel Core i7 3930K 6 x 3.20 GHz (Sandy Bridge-E)
64 GB DDR3-RAM
256 GB SSD (Samsung 830)
3000 GB S-ATA HDD
100 Mbps switch port
Unlimited Traffic
Only 109.99 EUR / month!
Setup-fee starting at 0 EUR depending on the contract period!

 

2. Contabo virtual private servers (VPS) - doubled performance at a lower price!

VPS M
1 CPU Core
4 GB RAM (guaranteed)
200 GB HDD
100 Mbps switch port
Unlimited Traffic
Only 9.99 EUR / month!
Special introductory offer: 0 EUR setup-fee!

VPS L
2 CPU Cores
8 GB RAM (guaranteed)
400 GB HDD
100 Mbps switch port
Unlimited Traffic
only 16.99 EUR / month!
Special introductory offer: 0 EUR setup-fee!

VPS XL
4 CPU Cores
16 GB RAM (guaranteed)
800 GB HDD
100 Mbps switch port
Unlimited Traffic
Only 29.99 EUR / month!
Special introductory offer: 0 EUR setup-fee!

Posted by: Katharina | Tagged as: , , , , 8 Comments