Re: Q: Mirroring - what is the better way

On 13 Nov 1997 22:08:15 -0700, Pablo Sanchez <pablo@sgi.com> wrote: >Like most things you have tradeoffs... you can let Informix >handle the mirror but as been noted, the performance would >be slower than at the OS level. The person doing the >training obviously doesn't understand device drivers and >s/w layers... oh well... > >Another thing to consider is that with the OS (and depending >on the OS) you can plex to more than one device. The idea >here would be to break the plex and do a cold backup on >those devices and re-initiate the plex. This is a possibility, but you have to be aware of the processes using the partitions. I can't speak about Informix (yet), but the db system I'm currently using would fail under a restore from the cold backup you describe. The database files would be logically corrupted. Here's something else to consider: hardware mirroring. I'm using an HP Model 20 RAID Array (a re-labeled Data General Clarion array) with pretty good success. I've had 1 module fail, and no one even noticed that it went out. The Informix SysAdmin class I took in August indicated that hardware mirroring was preferable, with OS and Informix mirroring in second place. Jeff Kalchik ---------------------------------------- Views expressed are my own, not necessarily 3COM's.