Hi, we do operate multiple instances (of possibly different versions) of Cassandra on rather thick nodes. The only problem we encountered so far was sharing same physical data disk among multiple instances - it proved to not be the best idea.Sharing of commitlog disks caused no troubles so far. Other than that, it works without any problems. We manage the instances by a set of helper scripts (which change the env variables, so "nodetool" and such operates on right instance) and puppet templates.
Jiri Horky On Thu, May 21, 2015 at 11:06 PM, Dan Kinder <dkin...@turnitin.com> wrote: > @James Rothering yeah I was thinking of container in a broad sense: either > full virtual machines, docker containers, straight LXC, or whatever else > would allow the Cassandra nodes to have their own IPs and bind to default > ports. > > @Jonathan Haddad thanks for the blog post. To ensure the same host does > not replicate its own data, would I basically need the nodes on a single > host to be labeled as one rack? (Assuming I use vnodes) > > On Thu, May 21, 2015 at 1:02 PM, Sebastian Estevez < > sebastian.este...@datastax.com> wrote: > >> JBOD --> just a bunch of disks, no raid. >> >> All the best, >> >> >> [image: datastax_logo.png] <http://www.datastax.com/> >> >> Sebastián Estévez >> >> Solutions Architect | 954 905 8615 | sebastian.este...@datastax.com >> >> [image: linkedin.png] <https://www.linkedin.com/company/datastax> [image: >> facebook.png] <https://www.facebook.com/datastax> [image: twitter.png] >> <https://twitter.com/datastax> [image: g+.png] >> <https://plus.google.com/+Datastax/about> >> <http://feeds.feedburner.com/datastax> >> >> <http://cassandrasummit-datastax.com/> >> >> DataStax is the fastest, most scalable distributed database technology, >> delivering Apache Cassandra to the world’s most innovative enterprises. >> Datastax is built to be agile, always-on, and predictably scalable to any >> size. With more than 500 customers in 45 countries, DataStax is the >> database technology and transactional backbone of choice for the worlds >> most innovative companies such as Netflix, Adobe, Intuit, and eBay. >> >> On Thu, May 21, 2015 at 4:00 PM, James Rothering <jrother...@codojo.me> >> wrote: >> >>> Hmmm ... Not familiar with JBOD. Is that just RAID-0? >>> >>> Also ... wrt the container talk, is that a Docker container you're >>> talking about? >>> >>> >>> >>> On Thu, May 21, 2015 at 12:48 PM, Jonathan Haddad <j...@jonhaddad.com> >>> wrote: >>> >>>> If you run it in a container with dedicated IPs it'll work just fine. >>>> Just be sure you aren't using the same machine to replicate it's own data. >>>> >>>> On Thu, May 21, 2015 at 12:43 PM Manoj Khangaonkar < >>>> khangaon...@gmail.com> wrote: >>>> >>>>> +1. >>>>> >>>>> I agree we need to be able to run multiple server instances on one >>>>> physical machine. This is especially necessary in development and test >>>>> environments where one is experimenting and needs a cluster, but do not >>>>> have access to multiple physical machines. >>>>> >>>>> If you google , you can find a few blogs that talk about how to do >>>>> this. >>>>> >>>>> But it is less than ideal. We need to be able to do it by changing >>>>> ports in cassandra.yaml. ( The way it is done easily with Hadoop or Apache >>>>> Kafka or Redis and many other distributed systems) >>>>> >>>>> >>>>> regards >>>>> >>>>> >>>>> >>>>> On Thu, May 21, 2015 at 10:32 AM, Dan Kinder <dkin...@turnitin.com> >>>>> wrote: >>>>> >>>>>> Hi, I'd just like some clarity and advice regarding running multiple >>>>>> cassandra instances on a single large machine (big JBOD array, plenty of >>>>>> CPU/RAM). >>>>>> >>>>>> First, I am aware this was not Cassandra's original design, and doing >>>>>> this seems to unreasonably go against the "commodity hardware" intentions >>>>>> of Cassandra's design. In general it seems to be recommended against (at >>>>>> least as far as I've heard from @Rob Coli and others). >>>>>> >>>>>> However maybe this term "commodity" is changing... my hardware/ops >>>>>> team argues that due to cooling, power, and other datacenter costs, >>>>>> having >>>>>> slightly larger nodes (>=32G RAM, >=24 CPU, >=8 disks JBOD) is actually a >>>>>> better price point. Now, I am not a hardware guy, so if this is not >>>>>> actually true I'd love to hear why, otherwise I pretty much need to take >>>>>> them at their word. >>>>>> >>>>>> Now, Cassandra features seemed to have improved such that JBOD works >>>>>> fairly well, but especially with memory/GC this seems to be reaching its >>>>>> limit. One Cassandra instance can only scale up so much. >>>>>> >>>>>> So my question is: suppose I take a 12 disk JBOD and run 2 Cassandra >>>>>> nodes (each with 5 data disks, 1 commit log disk) and either give each >>>>>> its >>>>>> own container & IP or change the listen ports. Will this work? What are >>>>>> the >>>>>> risks? Will/should Cassandra support this better in the future? >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> http://khangaonkar.blogspot.com/ >>>>> >>>> >>> >> > > > -- > Dan Kinder > Senior Software Engineer > Turnitin – www.turnitin.com > dkin...@turnitin.com >
