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Description of problem: We are seeing 'peth0: received packet with own address as source address' in dmesg while there is a HVM guest (which has vif) exist, this is not a duplicate of bug 509789, because it's cause by tap0 has the MAC addr 'FE:FF:FF:FF:FF:FF'. Version-Release number of selected component (if applicable): xen-3.0.3-125.el5 How reproducible: 100% Steps to Reproduce: 1. update xen to xen-3.0.3-125.el5 2. change network-script to 'network-bridge-mac' in /etc/xen/xend-config.sxp (network-script network-bridge-mac) 3. start a HVM guest with at least one vif attached Actual results: Will see lot of 'peth0: received packet with own address as source address' in dmesg. Expected results: No such messages reported. Additional info:
We can use printf "fe:%02x:%02x:%02x:%02x:%02x" \ $(($RANDOM % 256)) $(($RANDOM % 256)) $(($RANDOM % 256)) \ $(($RANDOM % 256)) $(($RANDOM % 256)) to create a random MAC address instead.
Created attachment 484180 [details] Generate random MAC Well, after discussing this with Paolo I used his code to generate the random MAC address and implemented this into tools/ioemu/target-i386-dm/qemu-ifup script to generate the MAC address randomly for any network interface of HVM guest and here's the example output in dom0: # ifconfig | grep tap tap0 Link encap:Ethernet HWaddr FE:7A:71:A2:29:0D tap1 Link encap:Ethernet HWaddr FE:4F:FE:4D:6E:D5 So the MAC addresses are generated randomly. I'm putting the patch here for testing but according to my testing I can see no messages as mentioned in description. Michal
Fix built into xen-3.0.3-126.el5
VERIFIED with xen-3.0.3-126.el5. The message of 'peth0: received packet with own address as source address' isn't present in dmesg after the fix applied. (Use 'network-bridge-mac' as the network-script in xend-config.sxp before test this.)
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: When an HVM guest was started with at least one virtual interface attached to it and with the network-script option set to "network-bridge-mac", a lot of "peth0: received packet with own address as source address" error messages appeared in the dmesg command output. With this update, a random MAC address is generated for TAP devices, and this bug no longer occurs.
I removed the technical notes, because the bug was introduced in the development of RHEL5.7 and was never in a released version.
Deleted Technical Notes Contents. Old Contents: When an HVM guest was started with at least one virtual interface attached to it and with the network-script option set to "network-bridge-mac", a lot of "peth0: received packet with own address as source address" error messages appeared in the dmesg command output. With this update, a random MAC address is generated for TAP devices, and this bug no longer occurs.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-1070.html