[DRBD-user] work with lvm2

[niko]

drbd version:8.2.6
OS:redhat enterprise 5.1
well,I'm a newbie,and I'm confused about the following result:
The server state:
#cat /proc/drbd
 1: cs:Connected st:Primary/Secondary ds:UpToDate/UpToDate C r---
    ns:98318 nr:0 dw:14 dr:99830 al:1 bm:6 lo:0 pe:0 ua:0 ap:0 oos:0

I bound the logic volume [lvmdrbd1] (96M) with /dev/drbd1
**************************************************************
[root at tfw drbd]# df -lh /dev/drbd1
Filesystem            Size  Used Avail Use% Mounted on
/dev/drbd1             93M   40M   49M  46% /drbd
**************************************************************
[root at tfw drbd]# df -lh /dev/VolGroup00/lvmdrbd1
Filesystem            Size  Used Avail Use% Mounted on
-                     232M  116K  232M   1% /dev
**************************************************************
[root at tfw /]# umount /drbd
[root at tfw /]# df -lh /dev/drbd1 
Filesystem            Size  Used Avail Use% Mounted on
-                     232M  116K  232M   1% /dev
**************************************************************

why ?
and my secondary node cann't be mounted:

#mount /dev/drbd1 /drbd/
mount:block device /dev/drbd1 is write-protected,mounting read-only
mount;Wrong medium type

BTW,my drbd.conf:

*************************************************************
global { 
  usage-count yes; 
}
common {
  protocol C;
}
resource r0 {
  on tfw{
    device    /dev/drbd1;
    disk      /dev/VolGroup00/lvmdrbd1;
    address   192.168.1.195:7789;
    flexible-meta-disk /dev/VolGroup00/lvmdrbdmd;
  }
  on tfw1{
    device    /dev/drbd1;
    disk      /dev/VolGroup00/lvmdrbd2;
    address   192.168.1.234:7789;
    meta-disk internal;
  }
}