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I/O error loading or writing tribble index file, ONLY on mounted folders (Ubuntu)

olingercolingerc LuxembourgMember

I am a bit stuck here. Any GATK tool I try (v3.5 and v3.7) that autocreates an index (e.g. ValidateVariants) fails in doing so with the following message:
MESSAGE: I/O error loading or writing tribble index file
However GATK correctly creates the vcf files (for example with UnifiedGenotyper) in the same folder.
I tried:

  • Manually creating/deleting/editing files in the same folder: No problem
  • All folders have complete rw permissions for all users
  • Copying the vcf file to a local drive and running ValidateVariants there correctly creates index file
  • After the error message, the idx file exists but is empty
  • Trying with different vcf files shows the same problem
  • Both the GATK.jar and reference files are local, only the vcf file is on a mounted drive

So in summary, somehow GATK does not like my mounted drives, but only for creating indexes. I am on ubuntu 16.04. Will check source code now.

Issue · Github
by Sheila

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Best Answer


  • olingercolingerc LuxembourgMember

    Creating index with igvtools on mounted drive works, but then GATK gives me the wollowing warning:
    INFO 09:42:58,319 RMDTrackBuilder - Writing Tribble index to disk for file /mnt/files-bioseq/bioseq-temporary/christophe/variants.vcf.idx WARN 09:42:58,347 RMDTrackBuilder - Unable to update index with the sequence dictionary for file /mnt/files-bioseq/bioseq-temporary/christophe/variants.vcf.idx; this will not affect your run of the GATK

  • olingercolingerc LuxembourgMember

    Using DEBUG log level I get the following 2 lines just before the error:
    DEBUG 09:52:23,957 RMDTrackBuilder - Creating Tribble index in memory for file /mnt/files-bioseq/bioseq-temporary/christophe/variants.vcf INFO 09:52:24,076 RMDTrackBuilder - Writing Tribble index to disk for file /mnt/files-bioseq/bioseq-temporary/christophe/variants.vcf.idx

  • olingercolingerc LuxembourgMember

    NFS shares work fine.
    Samba shares (via CIFS) do not work

  • olingercolingerc LuxembourgMember

    Hi Sheila,

    Indeed, that solved the situation. In the meantime I have moved to NFS shares so the problem was resolved in another way. However, good to know that there is a workaround for cifs shares.

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