Netbackup Appliance vs DataDomain
Hello,
Lets review your requirement
- Try to merge both domains, so both are member of the same domain acting as a cluster with 1 node at each site. This is possible but only one node will be active at any one time.
- Purchase storage or appliance to achieve the following:
With 1 storage\appliance at each site, have optimized duplication enabled so we have 2 copies of the backup, one at each site (storage\appliance) at all time. This to gradually go away from weekly tape vault and go over to a disk based solution. This is possible.
For point 1 above you have to understand that for this scenario your link between the two sites is extremely important as it connect the media servers and clients to the master. If you lose the link you'll not have backups/restores in the site where the master is passive. Just something to keep in mind.
Depending on the type of clustering you're referring to their are more considerations. The alternative to this is using AIR as mentioned above. With AIR you'll have to separate catalogs with the ability to selectively replicate (duplicate) the backup images between them. This allows you to restore images from one domain in the other if need be.
Please note that the AIR configuration does not protect you against any failures of the master, media or storage devices in one domain. If these service in one domain go down, the clients are not automatically protected by the other domain (its possible to reconfigure them but can be a bit of a task). So its good to have a level of high availability / redundancy in each doman to ensure backups continue.
Lately the DD/Appliance comparison is basically equal, almost all features exist for both. The only one that could be an issue is SAN Client. If you're going DD you''d need Linux media servers to be installed (if you're not running linux already).
HTH
I think this is not the case as you can very well restore from other domain. You just need to establish connection between the master/media server and the client and change the Master server entry in the BAR GUI. It shows the copies from other domain and then you can perform restore. I have tried and tested this.
Ok - assuming network team have considered latency and hops and possible QoS - then it might also be worth considering placing servers requiring low IO latency as near to the WAN ISL hop as possible, in an effort to reduce hop count - e.g. if the switches at each site carrying the LAN/WAN inter-site ISL have free ports - then maybe placing the servers utilising FSS on those "core" switches might result in lower IO reponse times than perhaps placing them on network edge LAN switches - but then maybe this also is not a problem if you have large wide ISL trunks between core and edge LAN switches at each site.
Something else to watch out for, maybe, is... if your inter-site fibre is not private dark fibre, then beware that some carriers splice different customers together, and sometimes the carriers will splice new customers in, or out, of shared inter-site carrier fibre - in which case it is usually best to use two different independent carriers with diverse routing - because these splicing "events / changes" can sometimes result in short-ish outages - and so also ensure that you have good communication with your carrier's "work teams" so that you can be informed of scheduled fibre works before they take place, and thus be sure that carrier A and carrier B do not engage in splicing events at the same time.
