https://community.hpe.com/t5/general/increase-decrease-of-emc-symmetrix-bcv-mirror-sets-to-provide/m-p/4440816#M3956 Hi,<BR /><BR />You can have upto 8 BCV to a standard volume but not at the same time.<BR /><BR />You can have only two BCV attached to a standard volume and u can have 8 clone attached to the standard volume at the same time,<BR />again there are two types of BCV's protected BCV and unprotected BCV as any standard device will have four mirror positions<BR /><BR />1. first mirror position is the device itself<BR /><BR />2. second mirror position is taken by RAID<BR />so a typical SYMM. device wil always use two mirror positions one for the device and second for the raid device(mirror)<BR />you cannot break this and use them as two seperate devices with that said two out of four is always used by any SYMM. device<BR />the remaining two mirror positions can be used for two purposes<BR /><BR />a. we can have a local BCV device attached to it in which case its 2 BCV max at the same time -- because only two mirror positions are available<BR /><BR />b. we can have an SRDF device in remote SYMM. two different symmetrix<BR />that is concurrent srdf<BR /><BR />3. we can have one BCV and one SRDF - one local copy and one remote copy there are the combinations available there is a fourth type called CLONE which will not use the mirror position so we can clone a standard device into 8 clones to 16 clones at a time without sacrificing any mirror positions.<BR /><BR />we cannot have 3 BCV's for a standard device<BR />because symmetrix does not support unprotected standard device Wed, 15 Jul 2009 10:43:23 GMT Sivakumar MJ._1 2009-07-15T10:43:23Z https://community.hpe.com/t5/general/increase-decrease-of-emc-symmetrix-bcv-mirror-sets-to-provide/m-p/4440815#M3955 Can anyone tell me if it is possible to increase and decrease the mirror levels of EMC Symmetrix BCV devices to provide additional copies of data?<BR /><BR />What I would like to do is have 3 BCV volumes but since I can only have one BCV for any standard what I am thinking of doing is making my BCV devices three way mirrors before they are synced to their standard devices. Then reducing the BCVs to having 0 mirrors. The EMC documentation states that the mirrors will then be new devices.<BR /><BR />I'm uncertain to if this process is repeated regularly will the mirrors always be assigned to the same device name/HP-UX special device files. Tue, 16 Jun 2009 17:06:37 GMT https://community.hpe.com/t5/general/increase-decrease-of-emc-symmetrix-bcv-mirror-sets-to-provide/m-p/4440815#M3955 Will Sterling 2009-06-16T17:06:37Z https://community.hpe.com/t5/general/increase-decrease-of-emc-symmetrix-bcv-mirror-sets-to-provide/m-p/4440816#M3956 Hi,<BR /><BR />You can have upto 8 BCV to a standard volume but not at the same time.<BR /><BR />You can have only two BCV attached to a standard volume and u can have 8 clone attached to the standard volume at the same time,<BR />again there are two types of BCV's protected BCV and unprotected BCV as any standard device will have four mirror positions<BR /><BR />1. first mirror position is the device itself<BR /><BR />2. second mirror position is taken by RAID<BR />so a typical SYMM. device wil always use two mirror positions one for the device and second for the raid device(mirror)<BR />you cannot break this and use them as two seperate devices with that said two out of four is always used by any SYMM. device<BR />the remaining two mirror positions can be used for two purposes<BR /><BR />a. we can have a local BCV device attached to it in which case its 2 BCV max at the same time -- because only two mirror positions are available<BR /><BR />b. we can have an SRDF device in remote SYMM. two different symmetrix<BR />that is concurrent srdf<BR /><BR />3. we can have one BCV and one SRDF - one local copy and one remote copy there are the combinations available there is a fourth type called CLONE which will not use the mirror position so we can clone a standard device into 8 clones to 16 clones at a time without sacrificing any mirror positions.<BR /><BR />we cannot have 3 BCV's for a standard device<BR />because symmetrix does not support unprotected standard device Wed, 15 Jul 2009 10:43:23 GMT https://community.hpe.com/t5/general/increase-decrease-of-emc-symmetrix-bcv-mirror-sets-to-provide/m-p/4440816#M3956 Sivakumar MJ._1 2009-07-15T10:43:23Z