--- /dev/null
+MGS Configuration Data
+^^^^^^^^^^^^^^^^^^^^^^
+
+[source,c]
+----
+#define MTI_NAME_MAXLEN 64
+struct mgs_config_body {
+ char mcb_name[MTI_NAME_MAXLEN]; /* logname */
+ __u64 mcb_offset; /* next index of config log to request */
+ __u16 mcb_type; /* type of log: CONFIG_T_[CONFIG|RECOVER] */
+ __u8 mcb_reserved;
+ __u8 mcb_bits; /* bits unit size of config log */
+ __u32 mcb_units; /* # of units for bulk transfer */
+};
+----
+
+The 'mgs_config_body' structure has information identifying to the MGS
+which Lustre file system the client is requesting configuration information
+from. 'mcb_name' contains the filesystem name (fsname). 'mcb_offset'
+contains the next record number in the configuration llog to process
+(see <<llog>> for details), not the byte offset or bulk transfer units.
+'mcb_bits' is the log2 of the units of minimum bulk transfer size,
+typically 4096 or 8192 bytes, while 'mcb_units' is the maximum number of
+2^mcb_bits sized units that can be transferred in a single request.
+
+[source,c]
+----
+struct mgs_config_res {
+ __u64 mcr_offset; /* index of last config log */
+ __u64 mcr_size; /* size of the log */
+};
+----
+
+The 'mgs_config_res' structure returns information describing the
+replied configuration llog data requested in 'mgs_config_body'.
+'mcr_offset' contains the last configuration record number returned
+by this reply. 'mcr_size' contains the maximum record index in the
+entire configuration llog. When 'mcr_offset' equals 'mcr_size' there
+are no more records to process in the log.
+