<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style>
</head>
<body lang="EN-GB" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt">We’ve recently been seeing quite a few node expels with messages of the form:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:30.882+0000: [W] The TCP connection to IP address 10.20.0.58 proto-pg-pf01.bear.cluster <c0n236> (socket 153) state is unexpected: state=1 ca_state=4 snd_cwnd=1 snd_ssthresh=5 unacked=5 probes=0
backoff=7 retransmits=7 rto=26496000 rcv_ssthresh=102828 rtt=6729 rttvar=12066 sacked=0 retrans=1 reordering=3 lost=5<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:30.882+0000: [I] tscCheckTcpConn: Sending debug data collection request to node 10.20.0.58 proto-pg-pf01.bear.cluster<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:30.882+0000: Sending request to collect TCP debug data to proto-pg-pf01.bear.cluster localNode<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:30.882+0000: [I] Calling user exit script gpfsSendRequestToNodes: event sendRequestToNodes, Async command /usr/lpp/mmfs/bin/mmcommon.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:24:52.611+0000: [E] Timed out in 300 seconds waiting for a commMsgCheckMessages reply from node 10.20.0.58 proto-pg-pf01.bear.cluster. Sending expel message.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">On the client node, we see messages of the form:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:31.101+0000: [N] sdrServ: Received Tcp data collection request from 10.10.0.33<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:19:31.102+0000: [N] GPFS will attempt to collect Tcp debug data on this node.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:24:52.838+0000: [N] sdrServ: Received expel data collection request from 10.10.0.33<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:24:52.838+0000: [N] GPFS will attempt to collect debug data on this node.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:25:02.741+0000: [N] This node will be expelled from cluster rds.gpfs.servers due to expel msg from 10.10.12.41 (b<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">ber-les-nsd01-data.bb2.cluster in rds.gpfs.server<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">2019-01-17_11:25:03.160+0000: [N] sdrServ: Received expel data collection request from 10.20.0.56<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">They always appear to be to a specific type of hardware with the same Ethernet controller, though the nodes are split across three data centres and we aren’t seeing link congestion on the links between them.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">On the node I listed above, it’s not actually doing anything either as the software on it is still being installed (i.e. it’s not doing GPFS or any other IO other than a couple of home directories).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Any suggestions on what “(socket 153) state is unexpected” means?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
</div>
</body>
</html>