I seem to have resolved this issue by installing the alternate kernel module for this chip set available from elrepo. # /sbin/lspci -nn | grep -i net . . . 01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03) . . . # /sbin/lspci -n | grep '01:00.0' 01:00.0 0200: 10ec:8168 (rev 03) Using the the device id (10ec:8168) to search: http://elrepo.org/tiki/DeviceIDs shows that this matches: r8168.ko pci 10EC:8168 kmod-r8168 # yum whatprovides kmod-r8168 . . . kmod-r8168-8.031.00-1.el6.elrepo.x86_64 : r8168 kernel module(s) Repo : elrepo Matched from: . . . # yum install kmod-r8168 . . . Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package kmod-r8168.x86_64 0:8.031.00-1.el6.elrepo will be installed --> Finished Dependency Resolution Dependencies Resolved ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: kmod-r8168 x86_64 8.031.00-1.el6.elrepo elrepo 73 k Transaction Summary ================================================================================ Install 1 Package(s) Total size: 73 k Installed size: 533 k Is this ok [y/N]: y Downloading Packages: . . . This seems to have cleared up the problem on both hosts but, only time will tell. -- *** E-Mail is NOT a SECURE channel *** James B. Byrne mailto:ByrneJB at Harte-Lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3