1. Hints for DPM Administration
Luca Vaccarossa
EGEE tutorial for administrators – 7 June 2007
INFN-CNAF Bologna

2. MONITORING DPM The main monitoring tool for DPM is dpm-qryconf
it displays the Disk Pool Manager conguration. For each pool, dpm-qryconf displays two lines.
The first one gives:
the pool name;
the default amount of space reserved for a le;
the threshold (in %) at which the garbage collector is started;
the threshold (in %) at which the garbage collector is stopped;
the default lifetime;
the default pin time;
EGEE tutorial for administrators
EGEE tutorial for administrators

3. MONITORING DPM 􀀀 the maximum lifetime; 􀀀 the maximum pin time;
􀀀 the File System Selection policy name;
􀀀 the Garbage Collection policy name;
􀀀 the Request Selection policy name;
􀀀 the group id if the pool is restricted;
􀀀 the space type: V (for Volatile), D (for Durable) or P (for Permanent);
􀀀 the Migration Policy name;
􀀀 the retention policy: R (for Replica), O (for Output) or C (for Custodial).
EGEE tutorial for administrators

4. MONITORING DPM The second one gives: 􀀀 the capacity of the disk pool.
􀀀 the amount of free space of the disk pool.
After each pool description, the filesystems belonging to the pool are listed giving:
􀀀 the server name;
􀀀 the filesystem name;
􀀀 the capacity;
􀀀 the amount of free space;
􀀀 the filesystem's status.
EGEE tutorial for administrators

5. MONITORING DPM
Another useful tool for retrive information is dpns-getacl.
It gets the Access ControlList associated with a DPNS directory/file.
For each path, it displays:
􀀀 the fille name;
􀀀 owner;
􀀀 the group;
􀀀 the Access Control List (ACL) if present.
If a directory has a default ACL, dpns-getacl also displays the default ACL. Regular files cannot have default ACLs.
EGEE tutorial for administrators

6. MONITORING DPM The output looks like: # file: filename
# owner: username
# group: groupname
user::perm
user:uid:perm
group::perm
group:gid:perm
mask:perm
other:perm
default:user::perm
default:user:uid:perm
default:group::perm
default:group:gid:perm
default:mask:perm
default:other:perm
EGEE tutorial for administrators

7. Further Informations (Requirements)
Performance and Status informations (Requirements):
capacity of the filesystems RDONLY;
amount of reserved space;
number of transfers for each file;
number of requests for each file;
number of requests processed;
number of movements on each pool;
number of active users;
number of files per VO;
amount of occupied space per VO/role/user;
amount of occupied space for each directory/file;
max accesibility latency, i.e. maximal time it will take the system to get any fille ready for transfer.
EGEE tutorial for administrators
EGEE tutorial for administrators

8. Answers on Requirements
dpm-qryconf does not report the space in read-only pool since they are considered not managed by the system. It should be easy for a tool to add that space.
The problem reported about the handling of full file systems has been cured in DPM now in production. Sites are encouraged to upgrade.
In DPM (in certification) there is an option on dpm-qryconf that reports explicit VOMS roles/groups and not virtual GID. Therefore the space reported can be accounted to specific VOMS roles/groups.
The space occupied by a single user can be reported. However this implies a schema change in the internal DPM DB. Therefore such a change can be implemented with DPM 1.7.n.
EGEE tutorial for administrators
EGEE tutorial for administrators

9. Answers on Requirements
Max accessibility latency can be provided again with DPM 1.7.n.
Amount of reserved space can be reported probably already with DPM
Other sites have expressed no interest in having reported the number of files per VO. Is there a use case for such a request ? It could be made available with DPM 1.7.n.
dpns-du is already available but not distributed since it is a quite expensive operation for the system and can degrade the performance. This could can be made available to sysadmins if needed.
EGEE tutorial for administrators

10. References https://twiki.cern.ch/twiki/bin/view/LCG/DpmAdminGuide
EGEE tutorial for administrators