One of my clients is currently investigating new hosting arrangements. It’s a bit of a complex process because there are lots of architectural issues relating to things such as the storage and backup of some terabytes of data and some serious computation on the data. Among other options we are considering cheap servers in the […]
I previously wrote about my first experiences with BTRFS . Since then I’ve been using BTRFS on more systems and have had good results. The main problem I want to address is with the reliability of RAID .
Requirements for a File Server
Now one of my clients has a need for a new fileserver. […]
There are some really good Network Attached Storage (NAS) devices on the market. NetApp is one company that is known for making good products . The advantage of a NAS is that you have a device with NVRAM for write-back caching, a filesystem that supports all the necessary features for best performance (NetApp developed their […]
Based on my investigation of RAID reliability  I have determined that BTRFS  is the Linux storage technology that has the best potential to increase data integrity without costing a lot of money. Basically a BTRFS internal RAID-1 should offer equal or greater data protection than RAID-6.
As BTRFS is so important and so […]
I’ve previously written Some Notes on DRBD  and a post about DRBD Benchmarking .
Previously I had determined that replication protocol C gives the best performance for DRBD, that the batch-time parameters for Ext4 aren’t worth touching for a single IDE disk, that barrier=0 gives a massive performance boost, and that DRBD gives a […]
Everyone agrees that backups are generally a good thing. But it seems that there is a lot less agreement about how backups should work. Here is a list of 5 principles of backup software that seem to get ignored most of the time:
(1/5) Backups should not be Application Specific
It’s quite reasonable for people […]
ZDNet has an insightful article by Robin Harris predicting the demise of RAID-6 due to the probability of read errors . Basically as drives get larger the probability of hitting a read error during reconstruction increases and therefore you need to have more redundancy to deal with this. He suggests that as of 2009 drives […]
DRBD is a system for replicating a block device across multiple systems. It’s most commonly used for having one system write to the DRBD block device such that all writes are written to a local disk and a remote disk. In the default configuration a write is not complete until it’s committed to disk locally […]
The Wiki documenting how to configure IP failover for Hetzner servers  is closely tied to the Linux HA project . This is OK if you want a Heartbeat cluster, but if you want manual failover or an automatic failover from some other form of script then it’s not useful. So I’ll provide the simplest […]
It’s widely regarded that to solve reliability problems you can just install a cluster. It’s quite obvious that if instead of having one system of a particular type you have multiple systems of that type and a cluster configured such that broken systems aren’t used then reliability will increase. Also in the case of routine […]