Red Hat Bugzilla – Bug 188038
MAC address handled improperly if given in UC Hex
Last modified: 2014-03-16 22:59:15 EDT
Description of problem:
system-config-network handles MAC addresses specified in upper-case hex improperly
Version-Release number of selected component (if applicable):
Always (on my machine)
Steps to Reproduce:
1. In the system-config-network gui, specify the MAC address, using upper case for HEX A..F
2. Run Network
Simple network connections such as ssh work fine.
http connections hang waiting on the server.
sftp succeeds in establishing a connection, but as soon as you run a command like ls, get or put, it
The only change necessary to get the network to work was to re-type the MAC address using lower-
case for the HEX (i.e. a..f).
This is reasonably serious, not because it will affect huge numbers of people (I guess resetting MAC
addresses isn't all that common, and using upper case takes more work so most people will use lower; I
got upper case because I was pasting from elsewhere, where it was listed in UC). The problem is, it's
such an obscure bug, it has taken a _huge_ amount of effort to find. I estimate I have spent probably 40
hours chasing this. Hopefully, at least people searching bugzilla in future will find it....
Just realised, this could be a driver bug rather than system-config-network. So my hardware information
is relevant: Marvell Yukon II on-board network interface, using the new (with kernel 2.6.16) sky2 default
driver. If I should be reporting this against sky2 instead, please let me know where I should do this.
what is the output of:
# /sbin/ip -o link
/etc/sysconfig/network-scripts/network-functions does the device renaming
according to HWADDR
This should be completely case-independent, as well.
I have to confess I now can't get it to fail. Switching to upper case does not
now lead to a recurrence of the freezing problem. It may be that the problem was
dependent on some state in the router. Whatever, this was a problem I had for
around a week, it resolved itself when I reset the mac address in lc, came back
again at the time when I reset it to uc, and finally disappeared when I set it
back to lc. But now, setting it to uc does not screw up the network connection.
FWIW, here is the /sbin/ip -o link output with uc:
2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000\
link/ether 00:15:f2:ae:f0:1b brd ff:ff:ff:ff:ff:ff
output is identical with lc. I will reset the status to 'works for me', in case
anyone else hits the same problem.