On Thu, Nov 10, 2011 at 3:27 PM, Subrahmanya Harve < subrahmanyaha...@gmail.com> wrote:
> I am facing an issue in 0.8.7 cluster - > > - I have two clusters in two DCs (rather one cross dc cluster) and two > keyspaces. But i have only configured one keyspace to replicate data to the > other DC and the other keyspace to not replicate over to the other DC. > Basically this is the way i ran the keyspace creation - > create keyspace K1 with > placement_strategy='org.apache.cassandra.locator.SimpleStrategy' and > strategy_options = [{replication_factor:1}]; > create keyspace K2 with > placement_strategy='org.apache.cassandra.locator.NetworkTopologyStrategy' > and strategy_options = [{DC1:2, DC2:2}]; > > I had to do this because i expect that K1 will get a large volume of data > and i do not want this wired over to the other DC. > > I am writing the data at CL=ONE and reading the data at CL=ONE. I am seeing > an issue where sometimes i get the data and other times i do not see the > data. Does anyone know what could be going on here? > > A second larger question is - i am migrating from 0.7.4 to 0.8.7 , i can > see that there are large changes in the yaml file, but a specific question > i had was - how do i configure disk_access_mode like it used to be in > 0.7.4? > > One observation i have made is that some nodes of the cross dc cluster are > at different system times. This is something to fix but could this be why > data is sometimes retrieved and other times not? Or is there some other > thing to it? > > Would appreciate a quick response. > disk_access_mode is no longer required. Cassandra attempts to detect 64 bit and set this correctly. If your systems are not running NTP and as a result their clocks are not in sync this can cause issues (with ttl columns). Your client machines must have correct time as well.