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Replication rule examples

Replica management is based on replication rules defined on data identifiers. A replication rule gets resolved and issues replica locks on the physical replicas.

A replication rule consists (besides other parameters) of a factor representing the numbers of replicas wanted and a Rucio Storage Element Expression that allows to select a set of probable RSEs to store the replicas.

The RSE Expression gets resolved into a set of RSEs, which are possible destination RSEs for the number of replicas the user wants to create.

Examples​

I want to have 2 replicas of first_dataset and second_dataset on Tier 1 RSEs​

username@host:~$ rucio rule add --copies 2 --rses 'tier=1' scope:first_dataset scope:second_dataset

To see all possible targets, the command rucio rse list can be used with the same RSE expression:

username@host:~$ rucio rse list --rses 'tier=1'

I want to have 2 replicas on whatever T2 RSEs in the UK but not in Glasgow​

username@host:~$ rucio rule add --copies 2 --rses 'tier=2&country=uk\site=GLASGOW' scope:first_dataset scope:second_dataset