https://issues.apache.org/jira/browse/MAPREDUCE-4398
is the bug that Robin is referring to. -- Arpit Gupta Hortonworks Inc. http://hortonworks.com/ On Oct 16, 2012, at 3:51 PM, "Goldstone, Robin J." <[email protected]> wrote: > This is similar to issues I ran into with permissions/ownership of > mapred.system.dir when using the fair scheduler. We are instructed to set > the ownership of mapred.system.dir to mapred:hadoop and then when the job > tracker starts up (running as user mapred) it explicitly sets the > permissions on this directory to 700. Meanwhile when I go to run a job as > a regular user, it is trying to write stuff into mapred.system.dir but it > can't due to the ownership/permissions that have been established. > > Per discussion with Arpit Gupta, this is a bug with the fair scheduler and > it appears from your experience that there are similar issues with > hadoop.tmp.dir. The whole idea of the fair scheduler is to run jobs under > the user's identity rather than as user mapred. This is good from a > security perspective yet it seems no one bothered to account for this in > terms of the permissions that need to be set in the various directories to > enable this. > > Until this is sorted out by the Hadoop developers, I've put my attempts to > use the fair scheduler on holdŠ > > Regards, > Robin Goldstone, LLNL > > On 10/16/12 3:32 PM, "Patai Sangbutsarakum" <[email protected]> > wrote: > >> Hi Harsh, >> Thanks for breaking it down clearly. I would say i am successful 98% >> from the instruction. >> The 2% is about hadoop.tmp.dir >> >> let's say i have 2 users >> userA is a user that start hdfs and mapred >> userB is a regular user >> >> if i use default value of hadoop.tmp.dir >> /tmp/hadoop-${user.name} >> I can submit job as usersA but not by usersB >> ser=userB, access=WRITE, inode="/tmp/hadoop-userA/mapred/staging" >> :userA:supergroup:drwxr-xr-x >> >> i googled around; someone recommended to change hadoop.tmp.dir to >> /tmp/hadoop. >> This way it is almost a yay way; the thing is >> >> if I submit as userA it will create /tmp/hadoop in local machine which >> ownership will be userA.userA, >> and once I tried to submit job from the same machine as userB I will >> get "Error creating temp dir in hadoop.tmp.dir /tmp/hadoop due to >> Permission denied" >> (as because /tmp/hadoop is own by userA.userA). vise versa if I delete >> /tmp/hadoop and let the directory be created by userB, userA will not >> be able to submit job. >> >> Which is the right approach i should work with? >> Please suggest >> >> Patai >> >> >> On Mon, Oct 15, 2012 at 3:18 PM, Harsh J <[email protected]> wrote: >>> Hi Patai, >>> >>> Reply inline. >>> >>> On Tue, Oct 16, 2012 at 2:57 AM, Patai Sangbutsarakum >>> <[email protected]> wrote: >>>> Thanks for input, >>>> >>>> I am reading the document; i forget to mention that i am on cdh3u4. >>> >>> That version should have the support for all of this. >>> >>>>> If you point your poolname property to mapred.job.queue.name, then you >>>>> can leverage the Per-Queue ACLs >>>> >>>> Is that mean if i plan to 3 pools of fair scheduler, i have to >>>> configure 3 queues of capacity scheduler. in order to have each pool >>>> can leverage Per-Queue ACL of each queue.? >>> >>> Queues are not hard-tied into CapacityScheduler. You can have generic >>> queues in MR. And FairScheduler can bind its Pool concept into the >>> Queue configuration. >>> >>> All you need to do is the following: >>> >>> 1. Map FairScheduler pool name to reuse queue names itself: >>> >>> mapred.fairscheduler.poolnameproperty set to 'mapred.job.queue.name' >>> >>> 2. Define your required queues: >>> >>> mapred.job.queues set to "default,foo,bar" for example, for 3 queues: >>> default, foo and bar. >>> >>> 3. Define Submit ACLs for each Queue: >>> >>> mapred.queue.default.acl-submit-job set to "patai,foobar users,adm" >>> (usernames groupnames) >>> >>> mapred.queue.foo.acl-submit-job set to "spam eggs" >>> >>> Likewise for remaining queues, as you need itŠ >>> >>> 4. Enable ACLs and restart JT. >>> >>> mapred.acls.enabled set to "true" >>> >>> 5. Users then use the right API to set queue names before submitting >>> jobs, or use -Dmapred.job.queue.name=value via CLI (if using Tool): >>> >>> http://hadoop.apache.org/docs/stable/api/org/apache/hadoop/mapred/JobConf >>> .html#setQueueName(java.lang.String) >>> >>> 6. Done. >>> >>> Let us know if this works! >>> >>> -- >>> Harsh J >
