今天在網(wǎng)上看到1個朋友問:為何在ASM存儲管理的方式下明明只設置了log_archive_dest_1來指定歸檔的路徑,卻在ASM下發(fā)現(xiàn)了兩處歸檔日志文件?(未開閃回)
我查了1些資料,認為是這樣的:
Every file created in ASM gets a system-generated filename, otherwise known as a fully qualified filename (FQFN). The fully qualified filename represents a complete path name in the ASM file system. An example of a fully qualified filename is:
+dgroup2/sample/controlfile/Current.256.541956473
You can use the fully qualified filename to reference (read or retrieve) an ASM file. ASM generates a fully qualified filename upon any request to create a file. A creation request cannot specify a fully qualified filename. Instead, it uses a simpler syntax to specify a file, such as an alias or just a disk group name. ASM then creates the file, placing it in the correct ASM “path” according to file type, and then assigns an appropriate fully qualified filename. If you specify an alias in the creation request, ASM also creates the alias so that it references the fully qualified filename.
最后ls -l 看了下ASM里這兩個目錄下的歸檔日志文件后發(fā)現(xiàn),確切就是這類情況:
Oracle不希望我們改這些文件的路徑,但我們熱中于做這個,而且ORacle自動產(chǎn)生的文件名不方便人為記憶并管理,估計oracle也意想到了這問題便也有了別名了。