Karl Can you capture the entire TCP conversation and see the MSS size. What is the other device?
Is the device recording the wireshark trace set to record jumbo frames? I have had VLAN information removed by Windows nic drivers when recording packet captures. Eric -----Original Message----- From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Karl Kingston Sent: Wednesday, November 17, 2010 12:50 PM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Jumbo Frames This is a multipart message in MIME format. --=_alternative 006201BF852577DE_= Content-Type: text/plain; charset="US-ASCII" Did that. We even ran a wireshark trace and ended up seeing frame sizes of 1514. From: Eric Schadow <escha...@davisvision.com> To: IBMVM@LISTSERV.UARK.EDU Date: 11/17/2010 12:40 PM Subject: Re: Jumbo Frames Sent by: The IBM z/VM Operating System <IBMVM@LISTSERV.UARK.EDU> Karl Check if jumbo frames are enabled on the switch the mainframe is plugged into. I think cisco switches need to be reloaded after changing the system MTU size to jumbo frames. For networking questions I tend to go right to a packet capture of some sort as the packets never lie - well almost never... Eric -----Original Message----- From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Karl Kingston Sent: Wednesday, November 17, 2010 12:30 PM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Jumbo Frames This is a multipart message in MIME format. --=_alternative 00602852852577DE_= Content-Type: text/plain; charset="US-ASCII" Forgot to mention: z/VM 5.4, SLES10SP2 is the linux flavor From: Karl Kingston <karlkings...@ongov.net> To: IBMVM@LISTSERV.UARK.EDU Date: 11/17/2010 12:26 PM Subject: Jumbo Frames Sent by: The IBM z/VM Operating System <IBMVM@LISTSERV.UARK.EDU> hi Folks.. We have a z10BC and I'm trying to get Jumbo Frames to work. I set the MTU in Linux to 8992. BUT when I transfer, I'm only seeing 20MB/s? Even if it's between 2 servers on the same box and subnet? Did I misconfigure something? --=_alternative 00602852852577DE_= Content-Type: text/html; charset="US-ASCII" <font size=2 face="sans-serif">Forgot to mention: z/VM 5.4, SLES10SP2 is the linux flavor</font> <br> <br> <br> <br> <br><font size=1 color=#5f5f5f face="sans-serif">From: </font><font size=1 face="sans-serif">Karl Kingston <karlkings...@ongov.net></font> <br><font size=1 color=#5f5f5f face="sans-serif">To: </font><font size=1 face="sans-serif">IBMVM@LISTSERV.UARK.EDU</font> <br><font size=1 color=#5f5f5f face="sans-serif">Date: </font><font size=1 face="sans-serif">11/17/2010 12:26 PM</font> <br><font size=1 color=#5f5f5f face="sans-serif">Subject: </font><font size=1 face="sans-serif">Jumbo Frames</font> <br><font size=1 color=#5f5f5f face="sans-serif">Sent by: </font><font size=1 face="sans-serif">The IBM z/VM Operating System <IBMVM@LISTSERV.UARK.EDU></font> <br> <hr noshade> <br> <br> <br><font size=2 face="sans-serif">hi Folks..</font><font size=3> <br> </font><font size=2 face="sans-serif"><br> We have a z10BC and I'm trying to get Jumbo Frames to work.</font><font size=3> <br> </font><font size=2 face="sans-serif"><br> I set the MTU in Linux to 8992. BUT when I transfer, I'm only seeing 20MB/s?</font><font size=3> <br> </font><font size=2 face="sans-serif"><br> Even if it's between 2 servers on the same box and subnet?</font><font size=3> <br> </font><font size=2 face="sans-serif"><br> Did I misconfigure something? </font><font size=3> <br> </font> <br> --=_alternative 00602852852577DE_=-- ------------------------------------------------------------------------ The information contained in this communication is intended only for the use of the recipient(s) named above. It may contain information that is privileged or confidential, and may be protected by State and/or Federal Regulations. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication, or any of its contents, is strictly prohibited. If you have received this communication in error, please return it to the sender immediately and delete the original message and any copy of it from your computer system. If you have any questions concerning this message, please contact the sender. ------------------------------------------------------------------------ --=_alternative 006201BF852577DE_= Content-Type: text/html; charset="US-ASCII" <font size=2 face="sans-serif">Did that. We even ran a wireshark trace and ended up seeing frame sizes of 1514. </font> <br> <br> <br> <br> <br> <br><font size=1 color=#5f5f5f face="sans-serif">From: </font><font size=1 face="sans-serif">Eric Schadow <escha...@davisvision.com></font> <br><font size=1 color=#5f5f5f face="sans-serif">To: </font><font size=1 face="sans-serif">IBMVM@LISTSERV.UARK.EDU</font> <br><font size=1 color=#5f5f5f face="sans-serif">Date: </font><font size=1 face="sans-serif">11/17/2010 12:40 PM</font> <br><font size=1 color=#5f5f5f face="sans-serif">Subject: </font><font size=1 face="sans-serif">Re: Jumbo Frames</font> <br><font size=1 color=#5f5f5f face="sans-serif">Sent by: </font><font size=1 face="sans-serif">The IBM z/VM Operating System <IBMVM@LISTSERV.UARK.EDU></font> <br> <hr noshade> <br> <br> <br><tt><font size=2>Karl<br> <br> Check if jumbo frames are enabled on the switch the mainframe is plugged<br> into.<br> <br> I think cisco switches need to be reloaded after changing the system MTU<br> size to jumbo frames.<br> <br> For networking questions I tend to go right to a packet capture of some<br> sort as the packets never lie - well almost never...<br> <br> Eric<br> <br> -----Original Message-----<br> From: The IBM z/VM Operating System [</font></tt><a href=mailto:IBMVM@LISTSERV.UARK.EDU><tt><font size=2>mailto:IBMVM@LISTSERV.UARK.EDU</font></tt></a><tt><font size=2>] On<br> Behalf Of Karl Kingston<br> Sent: Wednesday, November 17, 2010 12:30 PM<br> To: IBMVM@LISTSERV.UARK.EDU<br> Subject: Re: Jumbo Frames<br> <br> This is a multipart message in MIME format.<br> --=_alternative 00602852852577DE_=<br> Content-Type: text/plain; charset="US-ASCII"<br> <br> Forgot to mention: z/VM 5.4, SLES10SP2 is the linux flavor<br> <br> <br> <br> <br> From: Karl Kingston <karlkings...@ongov.net><br> To: IBMVM@LISTSERV.UARK.EDU<br> Date: 11/17/2010 12:26 PM<br> Subject: Jumbo Frames<br> Sent by: The IBM z/VM Operating System <IBMVM@LISTSERV.UARK.EDU><br> <br> <br> <br> hi Folks.. <br> <br> We have a z10BC and I'm trying to get Jumbo Frames to work. <br> <br> I set the MTU in Linux to 8992. BUT when I transfer, I'm only seeing <br> 20MB/s? <br> <br> Even if it's between 2 servers on the same box and subnet? <br> <br> Did I misconfigure something? <br> <br> <br> --=_alternative 00602852852577DE_=<br> Content-Type: text/html; charset="US-ASCII"<br> <br> <font size=2 face="sans-serif">Forgot to mention: &nbsp;z/VM 5.4, &nbsp;<br> SLES10SP2 is the linux flavor</font><br> <br><br> <br><br> <br><br> <br><br> <br><font size=1 color=#5f5f5f face="sans-serif">From: &nbsp; &nbsp;<br> &nbsp;<br> &nbsp;</font><font size=1 face="sans-serif">Karl Kingston<br> &lt;karlkings...@ongov.net&gt;</font><br> <br><font size=1 color=#5f5f5f face="sans-serif">To: &nbsp; &nbsp;<br> &nbsp;<br> &nbsp;</font><font size=1<br> face="sans-serif">IBMVM@LISTSERV.UARK.EDU</font><br> <br><font size=1 color=#5f5f5f face="sans-serif">Date: &nbsp; &nbsp;<br> &nbsp;<br> &nbsp;</font><font size=1 face="sans-serif">11/17/2010 12:26 PM</font><br> <br><font size=1 color=#5f5f5f face="sans-serif">Subject: &nbsp; &nbsp;<br> &nbsp; &nbsp;</font><font size=1 face="sans-serif">Jumbo Frames</font><br> <br><font size=1 color=#5f5f5f face="sans-serif">Sent by: &nbsp; &nbsp;<br> &nbsp; &nbsp;</font><font size=1 face="sans-serif">The IBM z/VM<br> Operating System &lt;IBMVM@LISTSERV.UARK.EDU&gt;</font><br> <br><br> <hr noshade><br> <br><br> <br><br> <br><font size=2 face="sans-serif">hi Folks..</font><font size=3> <br><br> </font><font size=2 face="sans-serif"><br><br> We have a z10BC and I'm trying to get Jumbo Frames to work.</font><font<br> size=3><br> <br><br> </font><font size=2 face="sans-serif"><br><br> I set the MTU in Linux to 8992. &nbsp; BUT when I transfer, I'm only<br> seeing<br> 20MB/s?</font><font size=3> <br><br> </font><font size=2 face="sans-serif"><br><br> Even if it's between 2 servers on the same box and subnet?</font><font<br> size=3><br> <br><br> </font><font size=2 face="sans-serif"><br><br> Did I misconfigure something? &nbsp;</font><font size=3> <br><br> </font><br> <br><br> --=_alternative 00602852852577DE_=--<br> <br> <br> <br> ------------------------------------------------------------------------ <br> The information contained in this communication is intended<br> only for the use of the recipient(s) named above. It may<br> contain information that is privileged or confidential, and<br> may be protected by State and/or Federal Regulations. If<br> the reader of this message is not the intended recipient,<br> you are hereby notified that any dissemination,<br> distribution, or copying of this communication, or any of<br> its contents, is strictly prohibited. If you have received<br> this communication in error, please return it to the sender<br> immediately and delete the original message and any copy<br> of it from your computer system. If you have any questions<br> concerning this message, please contact the sender.<br> ------------------------------------------------------------------------ <br> </font></tt> <br> --=_alternative 006201BF852577DE_=-- ------------------------------------------------------------------------ The information contained in this communication is intended only for the use of the recipient(s) named above. It may contain information that is privileged or confidential, and may be protected by State and/or Federal Regulations. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication, or any of its contents, is strictly prohibited. If you have received this communication in error, please return it to the sender immediately and delete the original message and any copy of it from your computer system. If you have any questions concerning this message, please contact the sender. ------------------------------------------------------------------------
