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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>Dear experts,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>My issue is that:<o:p></o:p></span></p><p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>I set up OpenStack in multi Nodes model, with ML2 Plugin and GRE mode.<o:p></o:p></span></p><p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>I created 2 VMs in the same Compute node. (1 Web and 1 DB).<o:p></o:p></span></p><p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>My App needs fully support packet 1500 Bytes.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>How can I configure Openstack to do that?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>----<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>I already configured:<o:p></o:p></span></p><p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l0 level1 lfo4'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>Set MTU of Ethernet_interface in VM <o:p></o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 style='margin-left:36.0pt;border-collapse:collapse'><tr><td width=312 valign=top style='width:233.75pt;border:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New";color:#1F497D'>VM1# ifconfig eth0 mtu 1600<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New";color:#1F497D'>VM2# ifconfig eth0 mtu 1600<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p></td><td width=708 valign=top style='width:530.75pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt'><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>root@cuong-vm-01:~# netstat -i<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Kernel Interface table<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>eth0 1600 0 15958 0 0 0 10317 0 0 0 BMRU<o:p></o:p></span></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0cm 0cm 1.0pt 0cm'><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>lo 65536 0 0 0 0 0 0 0 0 0 LRU<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>root@cuong-vm-02:~# netstat -i<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Kernel Interface table<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>eth0 1600 0 15936 0 0 0 10009 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>lo 65536 0 0 0 0 0 0 0 0 0 LRU</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p></o:p></span></p></td></tr></table><p class=MsoNormal style='margin-left:72.0pt'><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l0 level1 lfo4'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>Set MTU of every port in BR-INT to 1600Bytes<o:p></o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 style='margin-left:38.6pt;border-collapse:collapse'><tr><td width=926 valign=top style='width:694.2pt;border:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt'><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>root@controller:~# netstat -i<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Kernel Interface table<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>br-ex 1500 0 21680 0 0 0 2928 0 0 0 BRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>br-int </span><span style='font-size:9.0pt;font-family:"Courier New";color:red'>1600 </span><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>0 308 0 0 0 6 0 0 0 BRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>br-tun 1500 0 0 0 0 0 6 0 0 0 BRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>eth0 1500 0 483582 0 2 0 22859 0 0 0 BMPRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>eth1 1500 0 220 0 0 0 6 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>lo 65536 0 174389 0 0 0 174389 0 0 0 LRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qbr480003c8-57 1500 0 29 0 0 0 6 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qbr59db81a4-93 1500 0 46 0 0 0 6 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qvb480003c8-57 1500 0 15907 0 0 0 9877 0 0 0 BMPRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qvb59db81a4-93 1500 0 15773 0 0 0 10087 0 0 0 BMPRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qvo480003c8-57 </span><span style='font-size:9.0pt;font-family:"Courier New";color:red'>1600 </span><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>0 9877 0 0 0 15907 0 0 0 BMPRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>qvo59db81a4-93 </span><span style='font-size:9.0pt;font-family:"Courier New";color:red'>1600 </span><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>0 10087 0 0 0 15773 0 0 0 BMPRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>tap480003c8-57 1500 0 9995 0 0 0 15912 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>tap59db81a4-93 1500 0 10169 0 0 0 15764 0 0 0 BMRU<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Courier New";color:#1F497D'>virbr0 1500 0 0 0 0 0 0 0 0 0 BMU</span><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p></o:p></span></p></td></tr></table><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:red'>However, I clouldn’t ping from VM 01 to VM02 without fragment<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>root@cuong-vm-01:~# traceroute --mtu 172.16.10.13 <o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>traceroute to 172.16.10.13 (172.16.10.13), 30 hops max, 65000 byte packets<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>1 * F=1600 * *<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>2 * * *<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>3 * * *<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>4 * *^C<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>--- <o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>root@cuong-vm-02:~# ping -s 1500 -M do 172.16.10.12<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Courier New";color:red'>PING 172.16.10.12 (172.16.10.12) 1500(1528) bytes of data.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New";color:red'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Tahoma","sans-serif";color:red'>Thank you very much.<o:p></o:p></span></p></div></body></html>