Implicit space reservation in dCache SRM.


Create SpaceManager cell by adding the following dcache configuration command to one of the dcache batch files:

create diskCacheV111.services.SpaceManager SpaceManager \
"default -export \
-jdbcUrl=jdbc:postgresql://host/dcache \
-jdbcDriver=org.postgresql.Driver -dbUser=user -dbPass=pass"


Add the following  option should be added to the startup command of the srm cell in the srm batch file:
       -reserve-space=true \
        -space-reservation-strict=<true or false> \
Option -space-reservation-strict affects only the transfers from remote srm/gridftp system into the local storage system. If option is set to true, and the size of the file in the remote system is known, then transfer of more bytes then the known value will not be allowed (this for example might happen if source file has changed since we obtained TURL, or remote system reported incorrect file size).


Add the following two options to the gridftp doors startup commands in appropriate dcache batch files
             -space-reservation=true \
             -space-reservation-strict=<true or false> \

If you desire to prevent the gridftp door from receiving more data then were reserved and to prohibit transfers for which space was not reserved,  space-reservation-strict should l be set to true. Then the direct gridftp transfers to dcache will result in failure "space not reserved", only the gridftp transfers to TURL that were previously negotiated through SRM will succeed.


Author : Timur Perelmutov <timur@fnal.gov>
$Id: space.html,v 1.1 2005/08/29 11:59:50 timur Exp $