If the qeth interface was previously configured using system-config-network 1.6.0.el6.2, the "OPTIONS=" line needs to be manually added to /etc/sysconfig/network-scripts/ifcfg-<interface>.

After the configuration has been manually changed, activate the interface by either rebooting the system, or running the following commands:

# /sbin/znet_cio_free
# SUBSYSTEM="ccw" DEVPATH="bus/ccw/devices/<SUBCHANNEL 0>" /lib/udev/ccw_init
# ifup <interface>

A known issue in the bnx2 driver prevents BCM5709S network adapters from performing a vmcore core dump over NFS.

Intel 82575EB ethernet devices do not function in a 32 bit environment. To work around this issue, modify the kernel parameters to include the intel_iommu=off option.

Running the rds-ping command may fail, returning the error:

bind() failed, errno: 99 (Cannot assign requested address).

Note, also that this error may occur even with LOAD_RDS=yes set in /etc/rdma/rdma.conf. To work around this issue, load the rds-tcp module.

Running the command rds-stress on a client may result in the following error attempting to connect to the server:

connecting to <server IP address>:4000: No route to host
connect(<server IP address>) failed#

When configuring a network interface manually, including static IP addresses and search domains, it is possible that a search entry will not be propagated to /etc/resolv.conf. Consequently, short host names that do not include the domain name will fail to resolve. To workaround this issue, add a search entry manually to /etc/resolv.conf.

Under some circumstances, the NetworkManager panel applet cannot determine if a user has permission to enable networking. Consequently, after logging into the desktop, the "Enable Networking" and "Enable Wireless" checkboxes may be disabled. To work around this, run the following command as root:

touch /usr/share/polkit-1/actions/org.freedesktop.NetworkManager.policy

Alternatively, WiFi can be enabled using the command:

nmcli nm wifi on

or disabled using the command:

nmcli nm wifi off

Under some circumstances, the netcf command crashes, returning the error message:

Failed to initialize netcf
error: unspecified error

To work around this issue, set the following value in /etc/sysctl.conf:

   net.bridge.bridge-nf-call-iptables = 0

This issue presents when the augeas library (used by netcf) has trouble parsing one of the system config files that netcf needs to read or modify.

The default value of the Emulex lpfc module parameter, lpfc_use_msi, was 2 (MSI-X) on Red Hat Enterprise Linux 5.4. In Red Hat Enterprise Linux 6 this default is now set to 0 (INTx). This change causes the driver behavior to stop using MSI-X interrupt mode and reverts to using non-msi (INTx) interrupt mode. This change in defaults addresses apparent regressions in some hardware platforms, introduced when the default lpfc driver value was previously changed from 0 to 2 (which made MSI-X the default behavior).

If the lpfc module is behaving erratically, work around this issue by setting the lpfc module parameter lpfc_use_msi to 2.