Symptoms
On an AVE there is, by default, one network interface created name eth0.
After an AVE reboot, the eth0 interface is not present:
ifconfig eth0
eth0: error fetching interface information: Device not found
The list of available network interfaces confirms that eth0 is missing but a new, unconfigured interface called eth1 is present:
ifconfig -a
eth1 Link encap:Ethernet HWaddr 00:15:5D:C8:BC:B4
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1080
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:5258453 errors:0 dropped:0 overruns:0 frame:0
TX packets:5258453 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3043137745 (2902.1 Mb) TX bytes:3043137745 (2902.1 Mb)
The eth0 configuration file is present and has been unaltered:
ls -l /etc/sysconfig/network/ifcfg-eth0
-rw-r--r-- 1 root root 62 Jul 21 2003 /etc/sysconfig/network/ifcfg-eth0
cat /etc/sysconfig/network/ifcfg-eth0
STARTMODE='auto'
BOOTPROTO='static'
IPADDR='10.10.10.10/24'
NETMASK='255.255.255.0'
BROADCAST=''
ETHTOOL_OPTIONS=''
MTU=''
NAME=''
NETWORK=''
REMOTE_IPADDR=''
USERCONTROL='no'
There is no eth1 configuration file:
ls -l /etc/sysconfig/network/ifcfg-eth1
ls: cannot access /etc/sysconfig/network/ifcfg-eth1: No such file or directory
Device messages show that eth0 has been renamed to eth1:
dmesg | grep -i eth0
[ 1678.268338] udev: renamed network interface eth0 to eth1
The /etc/udev/rules.d/70-persistent-net.rules file has an entry for eth0 and an entry for eth1, both with different MAC addresses:
cat /etc/udev/rules.d/70-persistent-net.rules
# PCI device 0x8086:0x100f (e1000)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:50:56:80:94:f7", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:15:5D:C8:BC:B4", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
Cause
By default, Microsoft Hyper-V uses dynamic MAC address generation, which causes a different MAC address to be reassigned to the AVE virtual machine:
Resolution
1. Shut down the AVE.
2. Go to the Settings for the AVE in the Hyper-V manager.
3. Expand the settings for the "Network Adapter" in the left pane, and select "Advanced Features":
4. Select "Static" within the "MAC Address" box (as shown above). The address fields should already be populated with the default assigned by Hyper-V.
5. Press OK to save the settings.
6. Power on the AVE.
7. If there is a Data Domain attached to Avamar, use the command dpnctl start all to restart the Avamar services.
