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Recovery File Structures   «Prev 

Using 3 redo log file groups

multiplex redo logs with 3 groups
  1. g1_loga.ora: This is member 1 of group 1 stored on disk 1.
  2. g1_logb.ora: This is member 2 of group 1 stored on disk 2.
  3. g2_loga.ora: This is member 1 of group 2 stored on disk 1.
  4. g2_loga.ora: This is member 2 of group 2 stored on disk 2.
  5. g3_loga.ora: This is member 1 of group 3 stored on disk 1.
  6. g3_loga.ora: This is member 2 of group 3 stored on disk 2.
  7. LGWR: LGWR will write to members 1 & 2 of group 1. When a switch occurs, LGWR will write to members 1 & 2 of group 2. On the next switch LGWR will write to members 1 & 2 of group 3.
  8. disk 1: If disk 1 fails, LGWR will continue writing to disk 2 without database failure.
  9. disk 2: If disk 2 fails, LGWR will continue writing to disk 1 without database failure.
  10. redo group 1: There must be at least 2 members of the same size in each group. Each group should contain the same number of members.
  11. redo group 2: There must be at least 2 members of the same size in each group. Each group should contain the same number of members.
  12. redo group 3: There must be at least 2 members of the same size in each group. Each group should contain the same number of members.