Avamar：SQL 差异备份完成，但出现异常“在元数据文件中找不到differential_base_lsn值”

Avamar SQL 插件备份日志显示差异备份的以下行。

2018-06-06 11:13:39 avsql Warning <17378>: Private properties of resouce could not be resolved for Name.
2018-06-06 11:13:45 avsql Warning <43543>: Couldn't find the differential_base_lsn value in the metadata file. 
Due to the changes in this plugin version, it is recommended to take a FULL backup for the database '<sql-db-name>'.

出现上述警告的原因是，当检测到同一数据库的不同逻辑名称时，插件备份将“Differential_base_lsn”值留空。要检查“逻辑名称”，请运行 SQL 查询：

SELECT d.name AS DatabaseName,
       f.name AS LogicalName,
       f.physical_name AS PhysicalName,
       f.type_desc AS TypeofFile
FROM sys.master_files f
INNER JOIN sys.databases d ON d.database_id = f.database_id;

Here are the results:

DatabaseName	LogicalName	PhysicalName	TypeofFile
master		master	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\master.mdf	ROWS
master		mastlog	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\mastlog.ldf	LOG
tempdb		tempdev	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\tempdb.mdf	ROWS
tempdb		templog	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\templog.ldf	LOG
model		modeldev	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\model.mdf	ROWS
model		modellog	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\modellog.ldf	LOG
msdb		MSDBData	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\MSDBData.mdf	ROWS
msdb		MSDBLog	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\MSDBLog.ldf	LOG
db_1		DB_1	C:\SQL_AG_2\DB_1.mdf	ROWS
db_1		DB_1_log	C:\SQL_AG_2\DB_1_log.ldf	LOG
db1_2020	DB_1	C:\Recovery\db1_2020_data_0.mdf	ROWS
db1_2020	DB_1_log	C:\Recovery\db1_2020_log_0.ldf	LOG
feb13_restore	DB_1	C:\SQL_AG_2\feb13_restore_data_0.mdf	ROWS
feb13_restore	DB_1_log	C:\SQL_AG_2\feb13_restore_log_0.ldf	LOG
db_1_1		DB_1	C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\file	ROWS

当数据库存在不同的逻辑名称时，“Differential_base_lsn”值为空。
上述警告消息会导致备份完成但出现异常，但备份有效且可以完全还原。此问题已通过插件代码更改为不依赖于数据库逻辑名称得到解决。

可以安全地忽略该警告。
或者，联系 Avamar 支持部门获取外观问题已完全解决的插件程序热修复程序。