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-rw-r--r--Documentation/blockdev/drbd/DRBD-8.3-data-packets.svg588
-rw-r--r--Documentation/blockdev/drbd/DRBD-data-packets.svg459
-rw-r--r--Documentation/blockdev/drbd/README.txt16
-rw-r--r--Documentation/blockdev/drbd/conn-states-8.dot18
-rw-r--r--Documentation/blockdev/drbd/disk-states-8.dot16
-rw-r--r--Documentation/blockdev/drbd/drbd-connection-state-overview.dot85
-rw-r--r--Documentation/blockdev/drbd/node-states-8.dot14
7 files changed, 1196 insertions, 0 deletions
diff --git a/Documentation/blockdev/drbd/DRBD-8.3-data-packets.svg b/Documentation/blockdev/drbd/DRBD-8.3-data-packets.svg
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index 000000000000..f87cfa0dc2fb
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+++ b/Documentation/blockdev/drbd/DRBD-8.3-data-packets.svg
@@ -0,0 +1,588 @@
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+ id="tspan299">w_make_resync_request()</tspan>
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
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+ id="tspan347">w_e_end_csum_rs_req()</tspan>
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ id="tspan477">DRBD-8.3 data flow</tspan>
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+ id="tspan493">w_e_send_csum()</tspan>
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+ <tspan
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+ y="17606"
+ id="tspan609">drbd_endio_read_sec()</tspan>
+ </text>
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="18007"
+ id="tspan625">w_e_end_csum_rs_req()</tspan>
+ </text>
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+ style="font-size:318px;font-weight:400;fill:#000080;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="18507"
+ id="tspan641">got_IsInSync()</tspan>
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+ <tspan
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+ y="13877"
+ id="tspan657">Checksum based Resync, case in sync</tspan>
+ </text>
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+ id="tspan789">drbd_endio_read_sec()</tspan>
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+ <tspan
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+ y="25507"
+ id="tspan821">receive_OVReply()</tspan>
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+ y="26407"
+ id="tspan837">drbd_endio_read_sec()</tspan>
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+ <text
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+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="2026 2132 2293 2471 2648 2826 3004 3076 3254 3431 3503 3681 3787"
+ y="22602"
+ id="tspan1151">rs_begin_io()</tspan>
+ </text>
+ <text
+ id="text1165"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="1426 1532 1693 1871 2031 2209 2472 2649 2721 2899 2988 3166 3344 3416 3593 3699"
+ y="11302"
+ id="tspan1167">rs_complete_io()</tspan>
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+ <text
+ id="text1181"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="1526 1632 1793 1971 2131 2309 2572 2749 2821 2999 3088 3266 3444 3516 3693 3799"
+ y="18931"
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+ <text
+ id="text1197"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="1526 1632 1793 1971 2131 2309 2572 2749 2821 2999 3088 3266 3444 3516 3693 3799"
+ y="27231"
+ id="tspan1199">rs_complete_io()</tspan>
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+ <text
+ id="text1213"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16126 16232 16393 16571 16748 16926 17104 17176 17354 17531 17603 17781 17887"
+ y="7402"
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+ <text
+ id="text1229"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16127 16233 16394 16572 16749 16927 17105 17177 17355 17532 17604 17782 17888"
+ y="16331"
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+ id="text1245"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16127 16233 16394 16572 16749 16927 17105 17177 17355 17532 17604 17782 17888"
+ y="23302"
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+ <text
+ id="text1261"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16115 16221 16382 16560 16720 16898 17161 17338 17410 17588 17677 17855 18033 18105 18282 18388"
+ y="9302"
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+ </text>
+ <text
+ id="text1277"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16115 16221 16382 16560 16720 16898 17161 17338 17410 17588 17677 17855 18033 18105 18282 18388"
+ y="18331"
+ id="tspan1279">rs_complete_io()</tspan>
+ </text>
+ <text
+ id="text1293"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16126 16232 16393 16571 16731 16909 17172 17349 17421 17599 17688 17866 18044 18116 18293 18399"
+ y="25302"
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+</svg>
diff --git a/Documentation/blockdev/drbd/DRBD-data-packets.svg b/Documentation/blockdev/drbd/DRBD-data-packets.svg
new file mode 100644
index 000000000000..48a1e2165fec
--- /dev/null
+++ b/Documentation/blockdev/drbd/DRBD-data-packets.svg
@@ -0,0 +1,459 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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+<svg
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+ xmlns="http://www.w3.org/2000/svg"
+ version="1.0"
+ width="210mm"
+ height="297mm"
+ viewBox="0 0 21000 29700"
+ id="svg2"
+ style="fill-rule:evenodd">
+ <defs
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+ <path
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+ id="path221"
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+ transform="matrix(0.9788674,0.2044961,-0.2044961,0.9788674,0,0)"
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+ y="17807"
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+ id="text309"
+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="12199 12305 12483 12644 12821 12893 13054 13232 13410 13638 13816 13905 14083 14311 14489 14667 14845 15023 15184 15272 15378"
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ <tspan
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+ y="19573.385"
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+ <tspan
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+ <text
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+ y="4107.2339"
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="5505"
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+ <tspan
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+ y="7606"
+ id="tspan589">drbd_endio_write_sec()</tspan>
+ </text>
+ <text
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="8007"
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+ style="font-size:318px;font-weight:400;fill:#000080;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ <text
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+ style="font-size:423px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="4877"
+ id="tspan637">Regular mirrored write, 512-32K</tspan>
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ <path
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+ <path
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+ <path
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+ <text
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+ <text
+ id="text783"
+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
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+ <text
+ id="text799"
+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ id="tspan801">receive_DataRequest()</tspan>
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+ <text
+ id="text815"
+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ y="13607"
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+ </text>
+ <text
+ id="text831"
+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="12192 12421 12598 12776 12954 13132 13310 13487 13665 13843 14021 14110 14288 14465 14571 14749 14927 15033"
+ y="14008"
+ id="tspan833">w_e_end_data_req()</tspan>
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+ <desc
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+ <text
+ id="text847"
+ style="font-size:318px;font-weight:400;fill:#008000;font-family:Helvetica embedded">
+ <tspan
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+ <text
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+ style="font-size:423px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ style="font-size:318px;font-weight:400;fill:#008000;visibility:visible;font-family:Helvetica embedded">
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+ style="font-size:423px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
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+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
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+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="1626 1732 1893 2071 2231 2409 2672 2849 2921 3099 3188 3366 3544 3616 3793 3899"
+ y="22331"
+ id="tspan997">rs_complete_io()</tspan>
+ </text>
+ <text
+ id="text1011"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16027 16133 16294 16472 16649 16827 17005 17077 17255 17432 17504 17682 17788"
+ y="18402"
+ id="tspan1013">rs_begin_io()</tspan>
+ </text>
+ <text
+ id="text1027"
+ style="font-size:318px;font-weight:400;fill:#000000;visibility:visible;font-family:Helvetica embedded">
+ <tspan
+ x="16115 16221 16382 16560 16720 16898 17161 17338 17410 17588 17677 17855 18033 18105 18282 18388"
+ y="20331"
+ id="tspan1029">rs_complete_io()</tspan>
+ </text>
+</svg>
diff --git a/Documentation/blockdev/drbd/README.txt b/Documentation/blockdev/drbd/README.txt
new file mode 100644
index 000000000000..627b0a1bf35e
--- /dev/null
+++ b/Documentation/blockdev/drbd/README.txt
@@ -0,0 +1,16 @@
+Description
+
+ DRBD is a shared-nothing, synchronously replicated block device. It
+ is designed to serve as a building block for high availability
+ clusters and in this context, is a "drop-in" replacement for shared
+ storage. Simplistically, you could see it as a network RAID 1.
+
+ Please visit http://www.drbd.org to find out more.
+
+The here included files are intended to help understand the implementation
+
+DRBD-8.3-data-packets.svg, DRBD-data-packets.svg
+ relates some functions, and write packets.
+
+conn-states-8.dot, disk-states-8.dot, node-states-8.dot
+ The sub graphs of DRBD's state transitions
diff --git a/Documentation/blockdev/drbd/conn-states-8.dot b/Documentation/blockdev/drbd/conn-states-8.dot
new file mode 100644
index 000000000000..025e8cf5e64a
--- /dev/null
+++ b/Documentation/blockdev/drbd/conn-states-8.dot
@@ -0,0 +1,18 @@
+digraph conn_states {
+ StandAllone -> WFConnection [ label = "ioctl_set_net()" ]
+ WFConnection -> Unconnected [ label = "unable to bind()" ]
+ WFConnection -> WFReportParams [ label = "in connect() after accept" ]
+ WFReportParams -> StandAllone [ label = "checks in receive_param()" ]
+ WFReportParams -> Connected [ label = "in receive_param()" ]
+ WFReportParams -> WFBitMapS [ label = "sync_handshake()" ]
+ WFReportParams -> WFBitMapT [ label = "sync_handshake()" ]
+ WFBitMapS -> SyncSource [ label = "receive_bitmap()" ]
+ WFBitMapT -> SyncTarget [ label = "receive_bitmap()" ]
+ SyncSource -> Connected
+ SyncTarget -> Connected
+ SyncSource -> PausedSyncS
+ SyncTarget -> PausedSyncT
+ PausedSyncS -> SyncSource
+ PausedSyncT -> SyncTarget
+ Connected -> WFConnection [ label = "* on network error" ]
+}
diff --git a/Documentation/blockdev/drbd/disk-states-8.dot b/Documentation/blockdev/drbd/disk-states-8.dot
new file mode 100644
index 000000000000..d06cfb46fb98
--- /dev/null
+++ b/Documentation/blockdev/drbd/disk-states-8.dot
@@ -0,0 +1,16 @@
+digraph disk_states {
+ Diskless -> Inconsistent [ label = "ioctl_set_disk()" ]
+ Diskless -> Consistent [ label = "ioctl_set_disk()" ]
+ Diskless -> Outdated [ label = "ioctl_set_disk()" ]
+ Consistent -> Outdated [ label = "receive_param()" ]
+ Consistent -> UpToDate [ label = "receive_param()" ]
+ Consistent -> Inconsistent [ label = "start resync" ]
+ Outdated -> Inconsistent [ label = "start resync" ]
+ UpToDate -> Inconsistent [ label = "ioctl_replicate" ]
+ Inconsistent -> UpToDate [ label = "resync completed" ]
+ Consistent -> Failed [ label = "io completion error" ]
+ Outdated -> Failed [ label = "io completion error" ]
+ UpToDate -> Failed [ label = "io completion error" ]
+ Inconsistent -> Failed [ label = "io completion error" ]
+ Failed -> Diskless [ label = "sending notify to peer" ]
+}
diff --git a/Documentation/blockdev/drbd/drbd-connection-state-overview.dot b/Documentation/blockdev/drbd/drbd-connection-state-overview.dot
new file mode 100644
index 000000000000..6d9cf0a7b11d
--- /dev/null
+++ b/Documentation/blockdev/drbd/drbd-connection-state-overview.dot
@@ -0,0 +1,85 @@
+// vim: set sw=2 sts=2 :
+digraph {
+ rankdir=BT
+ bgcolor=white
+
+ node [shape=plaintext]
+ node [fontcolor=black]
+
+ StandAlone [ style=filled,fillcolor=gray,label=StandAlone ]
+
+ node [fontcolor=lightgray]
+
+ Unconnected [ label=Unconnected ]
+
+ CommTrouble [ shape=record,
+ label="{communication loss|{Timeout|BrokenPipe|NetworkFailure}}" ]
+
+ node [fontcolor=gray]
+
+ subgraph cluster_try_connect {
+ label="try to connect, handshake"
+ rank=max
+ WFConnection [ label=WFConnection ]
+ WFReportParams [ label=WFReportParams ]
+ }
+
+ TearDown [ label=TearDown ]
+
+ Connected [ label=Connected,style=filled,fillcolor=green,fontcolor=black ]
+
+ node [fontcolor=lightblue]
+
+ StartingSyncS [ label=StartingSyncS ]
+ StartingSyncT [ label=StartingSyncT ]
+
+ subgraph cluster_bitmap_exchange {
+ node [fontcolor=red]
+ fontcolor=red
+ label="new application (WRITE?) requests blocked\lwhile bitmap is exchanged"
+
+ WFBitMapT [ label=WFBitMapT ]
+ WFSyncUUID [ label=WFSyncUUID ]
+ WFBitMapS [ label=WFBitMapS ]
+ }
+
+ node [fontcolor=blue]
+
+ cluster_resync [ shape=record,label="{<any>resynchronisation process running\l'concurrent' application requests allowed|{{<T>PausedSyncT\nSyncTarget}|{<S>PausedSyncS\nSyncSource}}}" ]
+
+ node [shape=box,fontcolor=black]
+
+ // drbdadm [label="drbdadm connect"]
+ // handshake [label="drbd_connect()\ndrbd_do_handshake\ndrbd_sync_handshake() etc."]
+ // comm_error [label="communication trouble"]
+
+ //
+ // edges
+ // --------------------------------------
+
+ StandAlone -> Unconnected [ label="drbdadm connect" ]
+ Unconnected -> StandAlone [ label="drbdadm disconnect\lor serious communication trouble" ]
+ Unconnected -> WFConnection [ label="receiver thread is started" ]
+ WFConnection -> WFReportParams [ headlabel="accept()\land/or \lconnect()\l" ]
+
+ WFReportParams -> StandAlone [ label="during handshake\lpeers do not agree\labout something essential" ]
+ WFReportParams -> Connected [ label="data identical\lno sync needed",color=green,fontcolor=green ]
+
+ WFReportParams -> WFBitMapS
+ WFReportParams -> WFBitMapT
+ WFBitMapT -> WFSyncUUID [minlen=0.1,constraint=false]
+
+ WFBitMapS -> cluster_resync:S
+ WFSyncUUID -> cluster_resync:T
+
+ edge [color=green]
+ cluster_resync:any -> Connected [ label="resnyc done",fontcolor=green ]
+
+ edge [color=red]
+ WFReportParams -> CommTrouble
+ Connected -> CommTrouble
+ cluster_resync:any -> CommTrouble
+ edge [color=black]
+ CommTrouble -> Unconnected [label="receiver thread is stopped" ]
+
+}
diff --git a/Documentation/blockdev/drbd/node-states-8.dot b/Documentation/blockdev/drbd/node-states-8.dot
new file mode 100644
index 000000000000..4a2b00c23547
--- /dev/null
+++ b/Documentation/blockdev/drbd/node-states-8.dot
@@ -0,0 +1,14 @@
+digraph node_states {
+ Secondary -> Primary [ label = "ioctl_set_state()" ]
+ Primary -> Secondary [ label = "ioctl_set_state()" ]
+}
+
+digraph peer_states {
+ Secondary -> Primary [ label = "recv state packet" ]
+ Primary -> Secondary [ label = "recv state packet" ]
+ Primary -> Unknown [ label = "connection lost" ]
+ Secondary -> Unknown [ label = "connection lost" ]
+ Unknown -> Primary [ label = "connected" ]
+ Unknown -> Secondary [ label = "connected" ]
+}
+