Update maintenance.md

maintenance.md

@@ -65,6 +65,12 @@ As a reference from the documentation:
 ` ceph pg ls`
 more detailed
 `ceph pg dump`
+the output is:
+```
+PG     OBJECTS DEGRADED MISPLACED UNFOUND BYTES    OMAP_BYTES* OMAP_KEYS* LOG  STATE        SINCE VERSION     REPORTED    UP                    ACTING                SCRUB_STAMP                DEEP_SCRUB_STAMP           
+26.0         0        0         0       0        0           0          0 3079 active+clean    4m 24981'25879 24981:35819  [184,81,131,240]p184  [184,81,131,240]p184 2019-12-13 11:59:26.858317 2019-12-13 11:59:26.858317 
+```
+pg `26.0` has four replicas located in `[184,81,131,240]` and the primary is `184`.
 
 ### PG_DEGRADED (Degraded data redundancy: 10564/21718684 objects degraded (0.049%), 1 pg degraded)
 Find the problematic PG