2 Replies Latest reply on Jul 13, 2015 12:36 PM by kamalasekar

    Need expert advise on the best practices for configuring DAS



      I have 50 TB DAS and ELM 7TB Standlone (not a combo). I'm in the process of configuring my DAS with SIEM. can some one please tell me the best practices to add DAS in place.


      I wanted to use maximum storage of DAS, my data retention policy is One year along with redundancy. (I'm not going for ELM redindancy)


      How do I acheive redundancy of Logs with my ELM local storage and DAS.? Let's say- If my DAS is down, I should be able to get the logs from ELM local storage.

      I assume Mirroring ELM local storage with DAS will help me out. If I do so, I I'm afraid that I can only use 7 TB (becasue my ELM size is 7 TB) Once the data grow more that 7 TB the older data wil be earased in ELM local storage and mirror the same in DAS. Please correct me if I'm wrong.


      Is there any way that I can use my DAS as a primary Storage and ELM local as a secondard storage?


      In the storage pool, Can I mirror ELM Local storage and DAS with 3x the ELM size and keep the data in DAS unerased?




      Thanks in Advance, I'm waiting for experts reply.



        • 1. Re: Need expert advise on the best practices for configuring DAS


          You're kinda going in two different directions here, technically, as well as ...say compliance sake. There isn't an easy black and white answer.

          In general, how do 'YOU', define redundancy? I ask that not to be funny, but it does vary based on the engineer. In it's simplest form, I would recommend you configured the DAS as a RAID10, as we initially did. The caveat is, based on SLA's, and compliance that would not work, because all the drives were in the same chassis  and essentially only, "logically" separated.  As a temporary compromise, I setup up space on my SAN essentially setup a copy there. The client thought it was good.


          2. Using the above as a catalyst, I took it a step farther, and created a TRUE redundancy.  See, as I define redundancy, is similar to an HA cluster. One goes down the other peer component is there to take over. Thus, the above still wasn't redundant in the sense I speak of. We bought another ELM with another DAS50 and configured them as redundant. Thus if one goes down, logs may be redirected.


          As far as best practices are concerned, I like to look at the combo's as an example.... The true storage ALWAYS needs to be separated from the main device, thus no single point of failure. Secondly, you can also attach to elms to the same DAS chassis, as the chassis has two separate controllers.


          Hope this helps Kamal,

          Joe P.

          • 2. Re: Need expert advise on the best practices for configuring DAS

            Thanks Joe.. I got you.. this really helps me..will connect with you if I need any help.