How to use /dev/sdb with DRBD?

Question

Setting-up DRBD on CentOS 7 now.

The configuration is:

resource testdata1 {
    protocol C;
    on node1 {
            device /dev/drbd0;
            disk /dev/sdb;
            address 198.19.0.1:7788;
            meta-disk internal;
    }
    on node2 {
            device /dev/drbd0;
            disk /dev/sdb;
            address 198.10.0.2:7788;
            meta-disk internal;
    }
}

I have create the path with:

# mkdir -p /dev/sdb

When I run the initialize meta data command:

# drbdadm create-md testdata1

Got this message:

open(/dev/sdb) failed: Is a directory
open(/dev/sdb) failed: Is a directory
Command 'drbdmeta 0 v08 /dev/sdb internal create-md' terminated with exit code 20

Why?

Khirgiy Mikhail · Accepted Answer · 2017-07-19T05:13:09.647

1

Because /dev/sdb is a directory and isn't device. sda means scsi disk a, sdb - scsi disk b and etc. There are devices block special files for input and output operations witch are created by system automatically. You must have real hard disk or partition on it to create DRBD device.

edited Jul 19 '17 at 05:13

answered Jul 18 '17 at 05:39

Khirgiy Mikhail

332
1
5

1

`/dev/sdb` should not be a directory, it should be a block special file. – heemayl Jul 18 '17 at 05:42
@heemayl Thanks. I have corrected terminology. – Khirgiy Mikhail Jul 19 '17 at 05:14

How to use /dev/sdb with DRBD?

1 Answers1