Hello all -
Excellent questions - I will answer Clee's remote dedupe backup copy questions first, then address the 16 TB question second.
1) Do you need to license the deduplication for both media servers, or would a single deduplication option license cover this?
Each BE Media Server that you want to store deduplicated data would need a license for the Deduplication Option.
2) Is this optimized for replication so that only new deduped data gets sent to the remote location? In other words, are just the deduped delta's sent to the remote site, or does it do a full "dump" of the deduped data remotely each time?
It's optimized and only data that does not exist in the remote media server is sent. Consider a typical Remote Office -> Data Center configuration, with BE Media Servers at both the Remote Office and the Data Center. Data is backed up locally at the Remote Office and stored in the Remote Office's deduplicated storage folder. When you choose to set copy that data from Remote Office to Data Center, we actually do a deduplication job betwen the contents of the Remote Office's Deduplcated Storage Folder and the Data Center's Deduplicated Storage Folder, and only copy the deduplicated segments that are necesary.
3) If I have two sites, can I have them do Deduplicated Remote Backup Copy to each other so that each side can act as the offsite storage for the other, or does there have to be a "parent/child" or "central/remote" relationship set up?
There does not need to be a parent-child relationship. You can refer to each media server that way, but in reality, all Media Servers are peers. You *will* need to share catalogs between servers, and have each server be aware of each other's existence, which means you will need to use the Central Administration Server Option (CASO) to enable BE Media Servers to store each others' data. CASO is licensed ONCE per BE environemnt.
Next.... on to the 16 TB question...
There is a limit of 1 Deduplicated Storage Folder per Media Server. Since “common storage” is key to deduplicating across all backup data on that media server, it makes no sense from a deduplication effectiveness perspective to have multiple deduplicated storage folders per media server. The more data you have in the deduplicated storage folder to compare against, the better your dedupe ratios will be.
There is also a limit of 16 TB of *deduplicated data* per deduplicated storage folder. (Dehydrated = Deduplicated).
From Clee: For example, on site A, what if I have 10TB of logical data that dedupes down to 1 TB. On site B I have another 10TB of logical data that dedupes down to 1 TB. If I remote copy the site A data to site B and site B data to site A, I would have 20 TB (10 from A +10 from B) of logical data stored in each location. However, only 10TB of that data in each location is from a "local" backup. The other comes from a remote site backup copy. Have I exceeded the 16TB limit or not? (i.e. Would the remote backup copy data count toward the 16TB limit?)
The sum total of all deduplicated data stored in a single deduplication storage folder cannot be more than 16 TB. This limit is for all deduplicated/dehydrated data on that media server, regardless of how it entered the deduplicated storage folder. Only deduplicated data and not "logical" or "front-end" data is counted against this 16 TB limitation.
In the example you give above, Clee, *assuming* the 10-to-1 ratio holds when you transfer A->B and B->A, then the Media Server at Site A would hold 2 TB of deduplicated data, and the media server at Site B would hold 2 TB of deduplicated data. This is because we are deduplicating the *contents of the deduplicated storage folders* at Site A and Site B against each other.
I'll look into the FAQ and make sure it's clear that we refer to 16 TB of deduplicated data as the limit.
Let me know if this helps!
Thanks,
Aidan Finley
Sr. Product Manager, Backup Exec
