ASM diskgroup redundancy
From: Mladen Gogala <gogala.mladen_at_gmail.com>
Date: Wed, 7 Sep 2011 13:28:03 +0000 (UTC)
Message-ID: <pan.2011.09.07.13.28.03_at_gmail.com>
Why would anybody want to use any other redundancy than 'external'? The 'normal' redundancy means that there is 2-way mirroring and 'high' redundancy means that there is 3-way mirroring. My servers are connected to SAN (HP EVA 8000) which does RAID 1+0, RAID-5 or RAID-6, as needed. There is also multipathing enabled, which means that there are 2 HBA's and that if one fails, the other one takes over. Significant investment was made into SAN with all those capabilities, 16G of NVRAM, storage virtualization, snapshots and many other goodies. A consultant is now telling me that I am doing things wrong because I settled for an external redundancy. Also, I keep voting file and OCR on an OCFS2 file system, precisely to avoid the local registry stuff. I am aware of the recommendation to keep everything on ASM but that complicates the install. Oracle licenses are expensive as it is, I have a limited number of CPU cores at my disposal and I have to make the best of it. Why would I need to waste CPU on ASM mirroring when the company has already paid for the device that can do it automatically, with its own CPU?
Date: Wed, 7 Sep 2011 13:28:03 +0000 (UTC)
Message-ID: <pan.2011.09.07.13.28.03_at_gmail.com>
Why would anybody want to use any other redundancy than 'external'? The 'normal' redundancy means that there is 2-way mirroring and 'high' redundancy means that there is 3-way mirroring. My servers are connected to SAN (HP EVA 8000) which does RAID 1+0, RAID-5 or RAID-6, as needed. There is also multipathing enabled, which means that there are 2 HBA's and that if one fails, the other one takes over. Significant investment was made into SAN with all those capabilities, 16G of NVRAM, storage virtualization, snapshots and many other goodies. A consultant is now telling me that I am doing things wrong because I settled for an external redundancy. Also, I keep voting file and OCR on an OCFS2 file system, precisely to avoid the local registry stuff. I am aware of the recommendation to keep everything on ASM but that complicates the install. Oracle licenses are expensive as it is, I have a limited number of CPU cores at my disposal and I have to make the best of it. Why would I need to waste CPU on ASM mirroring when the company has already paid for the device that can do it automatically, with its own CPU?
-- http://mgogala.byethost5.comReceived on Wed Sep 07 2011 - 08:28:03 CDT