If you look at the HCL under tape libraries (for instance for NetBackup 10 asee NBU 10 HCL - EMC Tape Libraraies - NetBackup 9 has similar support) you will see that the EMC ML3 tape libray is supported. With the Flex 5250 though, you will only be able to connect via fibre channel (SAS connectivity is not supported - as stated in the notes in the HCL).
Don't forget to check the installed tape drives for compatibilty as well.
Thanks, I will give my colleague a OK to buy the tape library.
Could you update the link in your post. When I try to open the link I get the following error;
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