8. Known problems and limitations


  • Instance snapshots sometimes fail. This leaves the instance in the suspended state. To work round this issue we recommend users power off their VM before taking a snapshot.
  • Child instances launched using the snapshot of existing parent instance does not have security group predefined as of parent instance, please select the appropriate security group for child instances before launching them.
  • Resizing between "standard" and other flavors will fail. Your virtual machines end up in an "error" state. Please contact us if this happens. We are looking into making this resize possible.
  • Creating large ephemeral disks for legacy flavors takes a long time. A newly launched (legacy flavor) instance with a large ephemeral disk will stay in the "Spawning" state for some time because of this.
  • Performance: For the full hpc-gen1 node flavour (16 cores) some slowdown has been observed with some codes when using more than 12 cores when compared to taito.csc.fi. Please report any performance regressions compared to taito to cloud-support@csc.fi.
  • Network: It's possible to add the same floating IP to multiple instances using the API. There is no warning or error. The last API call is the one which takes effect.

Web interface

  • FTP uploads are not supported for adding images using a URL in the web interface (Horizon). However, the interface gives no indication of this, and the image remains in the Queued state forever. You can use HTTP sources instead.

EC2 tools (euca2ools)

  • EC2 is not supported at this time.
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