<html dir="ltr"><head></head><body style="text-align:left; direction:ltr;"><div>Hi All,</div><div><br></div><div>Can anyone please clarify what's the actual volume size limit for DRBD? The linbit's article dated 2012 says the current maximum is 1PiB, but when I'm trying to create a 3 node replication with 527TiB each, it gets me to the bitmap size error. </div><div><br></div><div>I have an assumption that overall bitmap size limit is divided for 2 replicas. Is there any technical reason behind it? Is there any other way to create this volume without splitting it up and joining by LVM on the top (LVM-> DRBD -> LVM)?</div><div><br></div><pre><font size="1"># drbdadm create-md r0</font></pre><pre><font size="1"><br></font></pre><pre><font size="1">Error: Bitmap for that device got too large.</font></pre><pre><font size="1">Command 'drbdmeta 0 v09 /dev/storage/data internal create-md 2' terminated with exit code 10</font></pre><div><br></div><pre><font size="1"># drbdadm dump all
# /etc/drbd.conf
global {
usage-count no;
}
common {
options {
auto-promote yes;
}
net {
protocol C;
max-buffers 8K;
}
disk {
disk-barrier no;
disk-flushes no;
md-flushes no;
disk-drain yes;
resync-rate 2G;
c-plan-ahead 0;
}
}
# resource r0 on sgpplhan01: not ignored, not stacked
# defined at /etc/drbd.d/r0.res:1
resource r0 {
volume 0 {
device /dev/drbd0 minor 0;
disk /dev/storage/data;
meta-disk internal;
}
on node01 {
node-id 1;
address ipv4 172.16.1.1:7788;
}
on </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">02 {</span><br><font size="1"> node-id 2;
address ipv4 172.16.2.1:7788;
}
on </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">03 {</span><br><font size="1"> node-id 3;
address ipv4 172.16.3.1:7788;
}
connection {
host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">01 address ipv4 172.16.1.1:7788;</span><br><font size="1"> host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">02 address ipv4 172.16.2.2:7788;</span><br><font size="1"> }
connection {
host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">01 address ipv4 172.16.1.2:7788;</span><br><font size="1"> host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">03 address ipv4 172.16.3.1:7788;</span><br><font size="1"> }
connection {
host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">02 address ipv4 172.16.2.1:7788;</span><br><font size="1"> host </font><span style="font-size: x-small;">node</span><span style="font-size: x-small;">03 address ipv4 172.16.3.2:7788;</span><br><font size="1"> }
}</font>
</pre><pre><font size="1"><br></font></pre><pre><font size="1"># lsblk</font></pre><pre><font size="1"><br></font></pre><pre></pre><pre><font size="1">NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 109.2T 0 disk
└─storage-data 253:3 0 527.6T 0 lvm
sdb 8:16 0 109.2T 0 disk
└─storage-data 253:3 0 527.6T 0 lvm
sdc 8:32 0 109.2T 0 disk
└─storage-data 253:3 0 527.6T 0 lvm
sdd 8:48 0 109.2T 0 disk
└─storage-data 253:3 0 527.6T 0 lvm
sdf 8:80 0 953.9G 0 disk
├─sdf1 8:81 0 200M 0 part /boot/efi
├─sdf2 8:82 0 1G 0 part /boot
└─sdf3 8:83 0 952.7G 0 part
├─centos-root 253:0 0 50G 0 lvm /
├─centos-swap 253:1 0 31.3G 0 lvm [SWAP]
└─centos-home 253:2 0 871.3G 0 lvm /home
sdg 8:96 0 91T 0 disk
└─storage-data 253:3 0 527.6T 0 lvm </font>
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