Forward to Long Term Archive

Forward the studies to external archive, do Storage Commit, and only delete objects of studies on original archive which are retrievable from external archive, if usable space fell below configurable threshold.

Configuration

• Configure auto-deletion of objects as explained in Deletion of least recently accessed studies. Just add an extra attribute/field-value on Storage system using archive UI (External Retrieve AET) or using LDAP (dcmExternalRetrieveAET) and its value should be the AE title of the system from where the objects can be retrieved.
• Configure auto-forwarding of objects as explained in Forwarding of received instances. Just add an extra attribute/field-value on Export Rule using archive UI (Property) or using LDAP (dcmProperty) and set its value as SendingApplicationEntityTitle!=<AE title>. The <AE title> is the value as explained in the point above.
• Refer Archive as SCU to understand how DCMQRSCP acts as a Storage Commitment SCP required for this feature

Testing

1. Export the studies and do storage commit. For testing purpose the dcmqrscp tool is used which supports the storage commitment.

a. Start the dcmqrscp tool

    dcmqrscp -b DCMQRSCP:11113 --dicomdir /tmp/DICOMDIR

 Log snippet : 

    13:03:15,356 INFO  - Start TCP Listener on 0.0.0.0/0.0.0.0:11113

b. Store the objects of studies to DCM4CHEE archive

    storescu -c DCM4CHEE@localhost:11112 /path_to_study.dcm

 Log snippet : 

    13:04:05,124 INFO  - STORESCU->DCM4CHEE(1) >> 1:C-STORE-RSP[pcid=7, status=0H
     cuid=1.2.840.10008.5.1.4.1.1.1 - Computed Radiography Image Storage
     iuid=1.3.51.0.7.1265535119.17104.33870.32953.8838.26602.20894 - ?
     tsuid=1.2.840.10008.1.2.4.80 - JPEG-LS Lossless Image Compression

c. After the duration configured in export rule, check in the dcmqrscp tool window that the objects exported have been stored and also the storage commitment has been done. Log snippet :

    13:05:08,719 INFO  - DCMQRSCP<-DCM4CHEE(1) << 1:C-STORE-RSP[pcid=5, status=0H
      cuid=1.2.840.10008.5.1.4.1.1.1 - Computed Radiography Image Storage
      iuid=1.3.51.0.7.1265535119.17104.33870.32953.8838.26602.20894 - ?
      tsuid=1.2.840.10008.1.2.4.80 - JPEG-LS Lossless Image Compression  
    .....
    13:05:09,398 INFO  - DCMQRSCP<-DCM4CHEE(2) << 1:N-ACTION-RSP[pcid=1, status=0H
      cuid=1.2.840.10008.1.20.1 - Storage Commitment Push Model SOP Class
      iuid=1.2.840.10008.1.20.1.1 - Storage Commitment Push Model SOP Instance
      tsuid=1.2.840.10008.1.2 - Implicit VR Little Endian
    ......
    13:05:09,772 INFO  - DCMQRSCP->DCM4CHEE(3) >> 1:N-EVENT-REPORT-RSP[pcid=1, status=0H
      cuid=1.2.840.10008.1.20.1 - Storage Commitment Push Model SOP Class
      iuid=1.2.840.10008.1.20.1.1 - Storage Commitment Push Model SOP Instance
      tsuid=1.2.840.10008.1.2 - Implicit VR Little Endian

2. Objects of least recently accessed studies are deleted from storage system as usable space falls below threshold. One can see this in the server logs, once the value configured in dcmPurgeStoragePollingInterval has been reached. Log snippet :

    14:05:26,048 INFO  [org.dcm4chee.arc.delete.impl.PurgeStorageScheduler] (EE-ManagedScheduledExecutorService-default-Thread-3) Usable Space on file:///Z:/ below 400MB - start deleting 40.28928MB
    14:05:26,136 INFO  [org.dcm4chee.arc.delete.impl.PurgeStorageScheduler] (EE-ManagedScheduledExecutorService-default-Thread-3) Successfully delete objects of Study[pk=1918, uid=1.2.4.0.13.1.432252867.1552647.1, id=1552647.1] on file:///Z:/
    ....