<div dir="ltr">You might need to check on the physical nic card instead of br-ex or br-tun. You can disable lro on physical interface using "<span style="font-family:Consolas,Menlo,Monaco,'Lucida Console','Liberation Mono','DejaVu Sans Mono','Bitstream Vera Sans Mono','Courier New',monospace,sans-serif;white-space:inherit;font-size:13px;background-color:rgb(238,238,238)">ethtool -k ethX lro off"</span><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature"><div dir="ltr"><b style="font-size:12.8000001907349px;color:rgb(136,136,136)"><font size="2">Rahul Sharma</font></b><br style="font-size:12.8000001907349px;color:rgb(136,136,136)"><font size="1" style="color:rgb(136,136,136)"><i>MS in Computer Science, 2016</i><br>College of Computer and Information Science, Northeastern University<br>Mobile: 801-706-7860<br>Email: <a href="mailto:rahulsharmaait@gmail.com" target="_blank">rahulsharmaait@gmail.com</a><br>Linkedin: <a href="http://www.linkedin.com/in/rahulsharmaait" target="_blank">www.linkedin.com/in/rahulsharmaait</a></font><br></div></div></div>
<br><div class="gmail_quote">On Mon, Sep 28, 2015 at 2:48 AM, applyhhj <span dir="ltr"><<a href="mailto:applyhhj@163.com" target="_blank">applyhhj@163.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><u></u>
<div style="LINE-HEIGHT:1.3;BORDER-RIGHT-WIDTH:0px;MARGIN:12px;BORDER-TOP-WIDTH:0px;BORDER-BOTTOM-WIDTH:0px;BORDER-LEFT-WIDTH:0px" marginheight="0" marginwidth="0">
<div><font color="#000000" size="3" face="Times New Roman">Hi
Sharma,</font></div>
<div><font face="Times New Roman"> Thank you very much for your
reply. You really helped me a lot. After trying ping VM with larger packet, the
result shows that when set -s parameter to larger than 1430 VM can not be pinged
no matter throw external ips or internal ips. So I checked settings of both
physical network interfaces and virtual nic through ethtool -k command, there
are many differences between those nics. Firstly setting of eth0 in VM is
different from setting of br-tun(all bridges have the same setting). The setting
for bridge is as follows where bolded items are different from settings of eth0
in VM. I think the problem may caused by different setting of
<strong>tx-gre-segmentation </strong>but I am not sure and I do not know how to
change the setting to test. Do you or anyone else has any idea about this
problem? Thank you very much!!</font></div>
<div> </div>
<div>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">Features for br-tun: <u></u><u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">rx-checksumming: off [fixed]
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">tx-checksumming: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-checksum-ipv4: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-checksum-ip-generic: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-checksum-ipv6: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-checksum-fcoe-crc: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-checksum-sctp: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">scatter-gather: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-scatter-gather: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-scatter-gather-fraglist: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">tcp-segmentation-offload: on
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-tcp-segmentation: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-tcp-ecn-segmentation: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif"><span>
</span>tx-tcp6-segmentation: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">udp-fragmentation-offload: on
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">generic-segmentation-offload: on
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">generic-receive-offload: on
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">large-receive-offload: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">rx-vlan-offload: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-vlan-offload: on <u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">ntuple-filters: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">receive-hashing: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">highdma: on <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">rx-vlan-filter: off [fixed]
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">vlan-challenged: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-lockless: on [fixed]
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">netns-local: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">tx-gso-robust: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">tx-fcoe-segmentation: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-gre-segmentation: on
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-ipip-segmentation: on
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-sit-segmentation: on
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-udp_tnl-segmentation: on
<u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">fcoe-mtu: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><b><span lang="EN-US"><font face="Liberation Serif">tx-nocache-copy: off <u></u><u></u></font></span></b></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">loopback: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">rx-fcs: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">rx-all: off [fixed] <u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">tx-vlan-stag-hw-insert: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">rx-vlan-stag-hw-parse: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">rx-vlan-stag-filter: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><span lang="EN-US"><font face="Liberation Serif">l2-fwd-offload: off [fixed]
<u></u><u></u></font></span></p>
<p style="MARGIN:0cm 0cm 0pt" class="MsoNormal"><a name="15012b6d0563908f___DdeLink__96_1106448133"></a><span lang="EN-US"><font face="Liberation Serif">busy-poll: off
[fixed]<u></u><u></u></font></span></p></div>
<div> </div>
<div> </div>
<div>Regards</div>
<div>hjh</div>
<div> </div>
<div align="left"><font color="#c0c0c0" size="2" face="Verdana">2015-09-28</font></div>
<div align="left"><font size="2" face="Verdana">
<hr style="WIDTH:122px;min-height:2px" align="left" size="2"><span class="HOEnZb"><font color="#888888">
</font></span></font></div><span class="HOEnZb"><font color="#888888">
<div align="left"><font color="#c0c0c0" size="2" face="Verdana"><span>applyhhj</span></font></div>
<div><font size="2" face="Verdana">
<hr>
</font></div>
<div><font size="2" face="Verdana"><strong>发件人：</strong>Rahul Sharma
<<a href="mailto:rahulsharmaait@gmail.com" target="_blank">rahulsharmaait@gmail.com</a>></font></div>
<div><font size="2" face="Verdana"><strong>发送时间：</strong>2015-09-28 02:41</font></div>
<div><font size="2" face="Verdana"><strong>主题：</strong>Re: [Openstack] Data
transmission failure between VM and outsidemachines</font></div>
<div><font size="2" face="Verdana"><strong>收件人：</strong>"Mike
Spreitzer"<<a href="mailto:mspreitz@us.ibm.com" target="_blank">mspreitz@us.ibm.com</a>></font></div>
<div><font size="2" face="Verdana"><strong>抄送：</strong>"applyhhj"<<a href="mailto:applyhhj@163.com" target="_blank">applyhhj@163.com</a>>,"openstack"<<a href="mailto:openstack@lists.openstack.org" target="_blank">openstack@lists.openstack.org</a>></font></div></font></span><div><div class="h5">
<div><font size="2" face="Verdana"></font> </div>
<div><font size="2" face="Verdana">
<div dir="ltr">Hi hjh,
<div><br></div>
<div>If you are able to ping to that particular instance (which I hope you would
be since the initial tcp handshake gets completed), the other thing which might
cause such an issue if the MTU size. We have also seen such issue when the
physical host's nic was unable to deal correctly with the fragmented packets.
You can test this by first sending ping packets, then increasing their size to
1500 and see if its successful. In our case, we had to disable Large Receive
Offload(LRO) on the nic card and then it worked fine. Other could be increasing
the MTU size on the nic itself. Do give it a try and see if it helps.</div>
<div><br></div>
<div>Thanks.</div>
<div class="gmail_extra"><br clear="all">
<div>
<div>
<div dir="ltr"><b style="COLOR:rgb(136,136,136);FONT-SIZE:12px"><font size="2">Rahul Sharma</font></b><br style="COLOR:rgb(136,136,136);FONT-SIZE:12px"><font style="COLOR:rgb(136,136,136)" size="1"><i>MS in Computer Science,
2016</i><br>College of Computer and Information Science, Northeastern
University<br>Mobile: <a href="tel:801-706-7860" value="+18017067860" target="_blank">801-706-7860</a><br>Email: <a href="mailto:rahulsharmaait@gmail.com" target="_blank">rahulsharmaait@gmail.com</a><br>Linkedin: <a href="http://www.linkedin.com/in/rahulsharmaait" target="_blank">www.linkedin.com/in/rahulsharmaait</a></font><br></div></div></div><br>
<div class="gmail_quote">On Sun, Sep 27, 2015 at 12:29 PM, Mike Spreitzer <span dir="ltr"><<a href="mailto:mspreitz@us.ibm.com" target="_blank">mspreitz@us.ibm.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote"><tt><font size="2">> From: "applyhhj" <<a href="mailto:applyhhj@163.com" target="_blank">applyhhj@163.com</a>></font></tt><br><tt><font size="2">>
To: "openstack" <<a href="mailto:openstack@lists.openstack.org" target="_blank">openstack@lists.openstack.org</a>></font></tt><br><tt><font size="2">> Date: 09/27/2015 11:16 AM</font></tt><br><tt><font size="2">>
Subject: [Openstack] Data transmission failure between VM and outside
machines</font></tt><span><br><tt><font size="2">> <br>> Hi, I have setup
the openstack cloud and launched VMs in the cloud. <br>> At first
everything went very well. But yesterday evening, due to <br>> some reasons
our lab lost power and all servers were shutdown. This <br>> morning I
turned on all nodes and try to connect to the VM by ssh <br>> but failed. I
used netstat to check the status of port 22. It shows <br>> that connection
between VM and machine in the external network can <br>> be established.
However the ssh process just stuck at <br>> SSH2_MSG_KEXINIT sent. Also I
setup a rabbitmq server in the VM and <br>> the same situation happened.
When connecting rabbitmq server through<br>> web ui, netstat shows that
connections have been established however<br>> the web browser can not get
any data from the server, it shows a <br>> blank page. Also I tried to ssh
from one VM to another VM through <br>> internal network, the <a href="http://192.168.1.0/24" target="_blank">192.168.1.0/24</a> network, similar
things <br>> happened. Does anyone know how to fix this problem? Thank you!
By <br>> the way the br-ex bridge can only be brought up manually, so after
<br>> boot the network node I brought up the br-ex bridge and restart all
<br>> relevant network services in network node. Please help me with this
<br>> problem. Thank you very much!!</font></tt><br><br></span><tt><font size="2">When faced with networking mysteries like that my next step is usually
to start taking packet traces at various points.</font></tt><br><br><tt><font size="2">Regards,</font></tt><br><tt><font size="2">Mike</font></tt><br><br>_______________________________________________<br>Mailing
list: <a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack" rel="noreferrer" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack</a><br>Post
to : <a href="mailto:openstack@lists.openstack.org" target="_blank">openstack@lists.openstack.org</a><br>Unsubscribe
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