Conference smurf::ase

1890.0. "Does ASE support database mirroring?" by TLAV02::SOMNUK () Thu Feb 20 1997 01:22

Dear All,

Normally in Trucluster ASE, we will do mirroring of data across the bus so 
that it can provide data availability. In case a disk in the mirror set is fail,
the operations can be continued. However, Informix people told me that Informix
DSA could not recognize such event and will leave Informix inoperable. Is it 
true?  So, Informix would like to use her own feature of database mirroring 
without using our LSM mirroring feature. In this case, if the data disk is fail
but we still have the mirror disk that created by Informix so how does 
TruCluster ASE is react to such event. Will database service stop or the 
operation is still continue?  The disk service is a raw device that contain
Informix database.

The proposed configuration:

AS8400, 4 CPU, 4 GB Mem (2 nodes cluster)
OS: Digital UNIX 4.0B
TruCluster V. 1.4
Informix DSA 7.2 UC 4
Data is approximately 500GB - 1 TB.

Best Regards,
Somnuk 

    I'm not sure I understand you question correctly.
    
    >we will do mirroring of data across the bus
    
    I assume this means you are using LSM mirroring with the mirror sets on
    2 seperate SCSI busses providing disk availability in case of a losing
    a SCSI bus.
    
    
    >However, Informix people told me that Informix DSA could not recognize
    >such even
    
    The question is: why should Informix DSA recognize this? An LSM
    mirrored disk looks like an ordinary disk to Informix and if the
    mirror breaks because a disk or a bus fails the Informix database
    should just keep on running as if nothing had happened.
    
    I'm not sure I got your point though
    
    	Martin