A few of us recently attended Velocity Conference in San Jose, CA. In the “hallway track sessions” a number people asked about the hardware that powers Basecamp, Campfire and Highrise.
All of our Ruby/Rails application roles run on Dell C Series 5220 servers. We chose C5220 servers because they provide high density, high performance, and low cost compute sleds at a decent cost point. The C5220 sleds replaced invidual Dell R710 servers which consumed a greater amount of power and rack space in addition to offering expandability we were not utilizing.
We use an 8 sled configuration with E31270 3.40GHz processors, 32/16G of ram, an LSI raid card and 2 non Dell SSDs. (For those of you thinking of ordering these … get the LSI raid card. The built in Intel raid is unreliable.) Each chassis with 8 sleds takes up 4U of rackspace: 3 for the chassis and 1 for cabling.
Job / Utility Servers
We use a combination of C6100 and C6220 servers to power our utility/jobs and API roles. We exclusively use the 4 sled version (of each) which means we get 4 “servers” in 2U. Each sled has 2x X5650 processors, 48-96G of ram, 2-6 ssds, and 4×1G or 1×10G network interfaces. This design allows to have up to 24 disks in a single chassis while consuming the same space as a single R710 server (which holds 8 disks max).
For Solr we run R710s filled with SSDs. Each instance varies, but a common configuration is 2x E5530 processors, 48G of ram, 4-8 ssds, and 4×1g network interfaces. For Elastic Search we run a mix of Poweredge 2950 servers and C 5220 sleds with 12-16G of ram and 2×400G ssds in a raid 1.
Database and Memcache/Redis Servers
For Database roles we use R710s with 2x X5670 processors, 1.2TB Fusion-IO duo cards and varying amounts of memory. (Varies based on the database size.) We also have a number of older R710s powering Memcache and Redis instances. Each of these has has 2x E5530 processors and 2-4 disks with 4×1G network interfaces.
We have around 400TB / 9 nodes of Isilon 36 and 72NL storage. We serve all of the user uploaded content off this storage with backups to S3.
Database servers run RHEL or Centos 6 while application and utility servers run Ubuntu LTS.