[solaris][veritas]请教几个术语

chao_ping

刚刚开始再看veritas volume manager的一些资料，有些不太理解，请教：
DMP: Dynamic Multipathing: 究竟是什么含义？
Plex 对应的概念在IBM 的LVM里面对应于什么概念？

clu65

DMP: Dynamic Multipathing. It is just link physical links in HP-UX LVM.

The idea is that you provide two physical path to the same physical device(in this case it is hard drive). In case of one controller failer, it will automaticall go through another links.

SUN Microsystem has AP(Alternate Pathing) similar to DMP.

Plex is made of SD(sub disks). And Volume is consisted of one or more plexes. I guess Plex is just like \"sub-mirror\" in HP-UX LVM. I guess IBM LVM is similar to HP-UX LVM.

Hope this might help.

You can go to the HP website to find \"VERITAS Volume Manager3.1 Migration Guide.pdf\". It tells you the difference between LVM and Veritas VM.

Hope this might help.

chao_ping

谢谢。
另外一个问题：
vxfs feature写到：
support for large file systems(up to 1 terabyte)
support for large files(up to 2 terabytes)

文件系统都只支持1Terabytes，为什么写到文件支持2Terabytes？
奇怪。

clu65

That is correct. It just tell you the theoretical limit for file size and file system size. It did not make much sense to me either. But in reality, you create very few file system larger than 100GB because performance issue.