Disk reservation: Difference between revisions
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The main commands for disk reservation are given below. Note that disk reservation only works with a node reservation of type deploy. Additionally, by default, reserving a node on grimoire will only grant access to the main disk (additional disks need to be reserved). | The main commands for disk reservation are given below. Note that disk reservation only works with a node reservation of type deploy. Additionally, by default, reserving a node on grimoire will only grant access to the main disk (additional disks need to be reserved). | ||
The maximum duration of a disk reservation is defined in the [[Grid5000:UsagePolicy#Rules_for_disks_reservations usage policy]]. | The maximum duration of a disk reservation is defined in the [[Grid5000:UsagePolicy#Rules_for_disks_reservations usage policy|Usage Policy]]. | ||
== Reserve disk and nodes at the same time == | == Reserve disk and nodes at the same time == |
Revision as of 13:17, 2 May 2017
Disk reservation is available for beta testing on the grimoire cluster in Nancy. Grimoire has eight nodes with five bookable disks on each node.
You can reserve hard disks, in order to store large datasets between your nodes reservations for example (and avoid moving data to nodes at the beginning of each nodes reservations).
How it works
When a job of type deploy starts, the disks you reserved are enabled by the RAID card of the node, and the other disks are disabled. Thus, reserved disks can only be accessed by the user who reserved them.
Main commands
The main commands for disk reservation are given below. Note that disk reservation only works with a node reservation of type deploy. Additionally, by default, reserving a node on grimoire will only grant access to the main disk (additional disks need to be reserved).
The maximum duration of a disk reservation is defined in the Usage Policy.
Reserve disk and nodes at the same time
You can reserve a node with its main disk on grimoire cluster
You can also reserve a node with all its disks
fnancy :
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oarsub -I -t deploy -l {"type='disk' or type='default' and disk_reservation_count > 0"}/host=1 |
disk_reservation_count represents the number of bookable disks on the node. At present only grimoire has bookable disks.
You can reserve nodes grimoire-1 and grimoire-2 with 1 disk per node
Reserve disks and nodes separately
First : reserve the disks
You can decide to reserve some disks for one week, and the corresponding nodes only when you want to carry out an experiment.
You can reserve two disks on grimoire-1 for one week, starting on January 1st
fnancy :
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oarsub -r "2018-01-01 00:00:00" -t noop -l {"type='disk' and host='grimoire-1.nancy.grid5000.fr'"}/host=1/disk=2,walltime=168 |
Or you can specify you want the first two disks of grimoire-2
fnancy :
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oarsub -r "2018-01-01 00:00:00" -t noop -l {"type='disk' and host='grimoire-2.nancy.grid5000.fr' and disk in ('1', '2')"}/host=1/disk=2,walltime=168 |
You can also reserve all disks of two nodes
fnancy :
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oarsub -r "2018-01-01 00:00:00" -t noop -l {"type='disk' and cluster='grimoire'"}/host=2/disk=ALL,walltime=168 |
Secondly: reserve the nodes
You can reserve in the usual way nodes grimoire-1 and grimoire-2 for 3 hours
fnancy :
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oarsub -I -t deploy -l {"host in ('grimoire-1.nancy.grid5000.fr', 'grimoire-2.nancy.grid5000.fr')"}/host=2,walltime=3 |
Data loss
Such as for your home directory, your data on the disks will not be backuped by Grid'5000. You must be cautious : several events such as a disk failure or a bad command on the node may delete your data.
Security issues
Unfortunately, it is not possible to avoid a malicious user to take control of the RAID card and therefore of the disks. If you have sensitive data and don't know how to protect them, you may contact the Grid'5000 technical team to help you. It is also your responsibility to erase the data on the disks you reserved, at the end of your experiment.