Figure 8-2 shows how the principal database appears in the
SSMS GUI.
Figure 8-2.MirrorTest, which is playing the principal role in the mirroring configuration,
is labeled as ???Principal, Synchronized,??? indicating that the mirror and the principal have
exactly the same data.
The principal is the point at which all data entry occurs. Even if a database is configured
for mirroring but the rest of the mirroring infrastructure is missing, damaged,
or disabled, users will still be able to get to the principal to enter data. If the components
other than the principal are down or disabled, the SSMS GUI will refer to the
principal as disconnected, as you can see in Figure 8-3.
Figure 8-3. The principal database as it appears in SSMS when the other components of the
mirroring solution are unavailable
CHAPTER 8 n DATABASE MIRRORING 197
If other components are causing the mirroring to fail, appropriate messages will
appear in the SQL Server error log, as shown in Figure 8-4. Luckily, these types of messages
won??™t fill the log on the principal node; other components of the mirroring solution
will alert the principal that they??™ve recovered on their own.
Pages:
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380