<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">
<div class="">I thought that this would be prevented by default because of spanning tree/BPDU, but it’s common practice to disable spanning tree for access ports (i.e. using portfast) so that may allow the loop to occur, so maybe just disable port-fast?</div>
<div class=""><br class="">
</div>
<div class="">Kind Regards</div>
<br class="">
<div class="">
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; " class="">
Stephen Welsh</div>
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; " class="">
CTO</div>
<br class="Apple-interchange-newline" style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">
<span><img height="16" width="100" apple-inline="yes" id="60FDE1E2-04EF-4A69-BB58-AFFAE08957FA" apple-width="yes" apple-height="yes" src="cid:CBBF0493-235C-43D2-A874-9FB3D95AF598@b2.unifiedfx.com" class=""></span>
</div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On 10 Nov 2016, at 13:35, Ahmed Elnagar <<a href="mailto:ahmed_elnagar@hotmail.com" class="">ahmed_elnagar@hotmail.com</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class="">That is not nice at all<span class="Apple-converted-space"> </span></span><span style="font-family: Wingdings; color: rgb(31, 73, 125);" class="">L</span><span style="color: rgb(31, 73, 125);" class=""><o:p class=""></o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class=""><o:p class=""> </o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class="">Did you figure out a way to prevent it from switch side?<o:p class=""></o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class=""><o:p class=""> </o:p></span></div>
<div class="">
<div style="border-style: solid none none; border-top-color: rgb(225, 225, 225); border-top-width: 1pt; padding: 3pt 0in 0in;" class="">
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<b class="">From:</b><span class="Apple-converted-space"> </span>Matthew Loraditch [<a href="mailto:MLoraditch@heliontechnologies.com" class="">mailto:MLoraditch@heliontechnologies.com</a>]<span class="Apple-converted-space"> </span><br class="">
<b class="">Sent:</b><span class="Apple-converted-space"> </span>Thursday, November 10, 2016 3:34 PM<br class="">
<b class="">To:</b><span class="Apple-converted-space"> </span>Ahmed Elnagar <<a href="mailto:ahmed_elnagar@hotmail.com" class="">ahmed_elnagar@hotmail.com</a>>; '<a href="mailto:cisco-voip@puck.nether.net" class="">cisco-voip@puck.nether.net</a>' <<a href="mailto:cisco-voip@puck.nether.net" class="">cisco-voip@puck.nether.net</a>><br class="">
<b class="">Subject:</b><span class="Apple-converted-space"> </span>RE: IP Phone Ports<o:p class=""></o:p></div>
</div>
</div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<o:p class=""> </o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class="">Yes it will create a loop. Not a fun time trying to track these things down. I’ve had some non-Cisco IP phones completely down a LAN.<o:p class=""></o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class=""><o:p class=""> </o:p></span></div>
<div class="">
<p class="MsoNormal" style="margin: 0in 0in 12pt; font-size: 11pt; font-family: Calibri, sans-serif;">
<span style="font-size: 10pt; color: rgb(31, 73, 125);" class="">Matthew G. Loraditch – CCNP-Voice, CCNA-R&S, CCDA<br class="">
Network Engineer<br class="">
Direct Voice: 443.541.1518</span><span style="color: rgb(31, 73, 125);" class=""><o:p class=""></o:p></span></p>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class=""><a href="https://www.facebook.com/heliontech?ref=hl" style="color: rgb(149, 79, 114); text-decoration: underline;" class=""><span style="font-size: 8pt; color: blue;" class="">Facebook</span></a></span><span style="font-size: 8pt; color: rgb(31, 73, 125);" class=""><span class="Apple-converted-space"> </span>|<span class="Apple-converted-space"> </span></span><span style="color: rgb(31, 73, 125);" class=""><a href="https://twitter.com/HelionTech" style="color: rgb(149, 79, 114); text-decoration: underline;" class=""><span style="font-size: 8pt; color: blue;" class="">Twitter</span></a></span><span style="font-size: 8pt; color: rgb(31, 73, 125);" class=""><span class="Apple-converted-space"> </span>|<span class="Apple-converted-space"> </span></span><span style="color: rgb(31, 73, 125);" class=""><a href="https://www.linkedin.com/company/helion-technologies?trk=top_nav_home" style="color: rgb(149, 79, 114); text-decoration: underline;" class=""><span style="font-size: 8pt; color: blue;" class="">LinkedIn</span></a></span><span style="font-size: 8pt; color: rgb(31, 73, 125);" class=""><span class="Apple-converted-space"> </span>|<span class="Apple-converted-space"> </span></span><span style="color: rgb(31, 73, 125);" class=""><a href="https://plus.google.com/+Heliontechnologies/posts" style="color: rgb(149, 79, 114); text-decoration: underline;" class=""><span style="font-size: 8pt; color: blue;" class="">G+</span></a><o:p class=""></o:p></span></div>
</div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<span style="color: rgb(31, 73, 125);" class=""><o:p class=""> </o:p></span></div>
<div class="">
<div style="border-style: solid none none; border-top-color: rgb(225, 225, 225); border-top-width: 1pt; padding: 3pt 0in 0in;" class="">
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<b class="">From:</b><span class="Apple-converted-space"> </span>cisco-voip [<a href="mailto:cisco-voip-bounces@puck.nether.net" style="color: rgb(149, 79, 114); text-decoration: underline;" class="">mailto:cisco-voip-bounces@puck.nether.net</a>]<span class="Apple-converted-space"> </span><b class="">On
Behalf Of<span class="Apple-converted-space"> </span></b>Ahmed Elnagar<br class="">
<b class="">Sent:</b><span class="Apple-converted-space"> </span>Thursday, November 10, 2016 8:28 AM<br class="">
<b class="">To:</b><span class="Apple-converted-space"> </span>'<a href="mailto:cisco-voip@puck.nether.net" class="">cisco-voip@puck.nether.net</a>' <<a href="mailto:cisco-voip@puck.nether.net" style="color: rgb(149, 79, 114); text-decoration: underline;" class="">cisco-voip@puck.nether.net</a>><br class="">
<b class="">Subject:</b><span class="Apple-converted-space"> </span>[cisco-voip] IP Phone Ports<o:p class=""></o:p></div>
</div>
</div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<o:p class=""> </o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
Dear all;<o:p class=""></o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<o:p class=""> </o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
I want to know what will happen if a user connect “by mistake” both the PC port and Switch port to the network switch? Will this create a loop? Anyone tried it before?<o:p class=""></o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<o:p class=""> </o:p></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">
<o:p class=""> </o:p></div>
</div>
<span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">_______________________________________________</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">
<span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">cisco-voip
mailing list</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">
<span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class=""><a href="mailto:cisco-voip@puck.nether.net" class="">cisco-voip@puck.nether.net</a></span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">
<span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class=""><a href="https://puck.nether.net/mailman/listinfo/cisco-voip" class="">https://puck.nether.net/mailman/listinfo/cisco-voip</a></span></div>
</blockquote>
</div>
<br class="">
</body>
</html>