The problem is between management interface Nexus 2248 and MDS9148, sometimes there is connection lost between this interfaces. To solve the problem immedialtly, it's necessary to put a PC or reboot Nexus2248. Then if you wait a moment the connexion back again. In attachment, the IOS version :
sh ver Cisco Nexus Operating System (NX-OS) Software TAC support: http://www.cisco.com/tac Copyright (c) 2002-2010, Cisco Systems, Inc. All rights reserved. The copyrights to certain works contained herein are owned by other third parties and are used and distributed under license. Some parts of this software are covered under the GNU Public License. A copy of the license is available at http://www.gnu.org/licenses/gpl.html.
Software BIOS: version 1.3.0 loader: version N/A kickstart: version 5.0(2)N1(1) system: version 5.0(2)N1(1) power-seq: version v1.2 BIOS compile time: 09/08/09 kickstart image file is: bootflash:/n5000-uk9-kickstart.5.0.2.N1.1.bin kickstart compile time: 10/15/2010 0:00:00 [10/15/2010 10:00:43] system image file is: bootflash:/n5000-uk220.127.116.11.N1.1.bin system compile time: 10/15/2010 0:00:00 [10/15/2010 11:34:05]
Hardware cisco Nexus5010 Chassis ("20x10GE/Supervisor") Intel(R) Celeron(R) M CPU with 2073416 kB of memory. Processor Board ID JAF1434BHBG