> On 15 Sep 2015, at 08:55, Adrian Bridgett <adr...@opensignal.com> wrote: > > Hi Sam, in short, no, it's a traditional install as we plan to use spot > instances and didn't want price spikes to kill off HDFS. > > We're actually doing a bit of a hybrid, using spot instances for the mesos > slaves, ondemand for the mesos masters. So for the time being, putting hdfs > on the masters (we'll probably move to multiple slave instance types to avoid > losing too many when spot price spikes, but for now this is acceptable). > Masters running CDH5.
It's incredibly dangerous using hdfs NNs on spot vms; a significant enough spike will lose all of them in one go, and there goes your entire filesystem. Have a static VM, maybe even backed by EBS. If you look at Hadoop architectures from Hortonworks, Cloudera and Amazon themselves, the usual stance is HDFS on static nodes, spot instances for compute only > > Using hdfs://current-hdfs-master:8020 works fine, however using > hdfs://nameservice1 fails in the rather odd way described (well, more that > the workaround actually works!) I think there's some underlying bug here > that's being exposed. this sounds an issue orthogonal to spot instances. Maybe related to how JVMs cache DNS entries forever? --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org
