A bug in previous versions of openmpi and lam may prevent you from upgrading these packages. This same bug may cause up2date to fail when upgrading all packages.
This bug manifests in the following error when attempting to upgrade openmpi or lam:
error: %preun(openmpi-[version]) scriptlet failed, exit status 2
This bug also manifests in the following error (logged in /var/log/up2date) when attempting to upgrade all packages through up2date:
up2date Failed running rpm transaction - %pre %pro failure ?.
As such, you need to manually remove older versions of openmpi and lam first in order to avoid these errors. To do so, use the following rpm command:
rpm -qa | grep '^openmpi-\|^lam-' | xargs rpm -e --noscripts --allmatches
When a LUN is deleted on a configured storage system, the change is not reflected on the host. In such cases, lvm commands will hang indefinitely when dm-multipath is used, as the LUN has now become stale.
To work around this, delete all device and mpath link entries in /etc/lvm/.cache specific to the stale LUN. To find out what these entries are, run the following command:
ls -l /dev/mpath | grep
<stale LUN>
For example, if is 3600d0230003414f30000203a7bc41a00, the following results may appear:
<stale LUN>
lrwxrwxrwx 1 root root 7 Aug 2 10:33 /3600d0230003414f30000203a7bc41a00 -> ../dm-4 lrwxrwx--rwx 1 root root 7 Aug 2 10:33 /3600d0230003414f30000203a7bc41a00p1 -> ../dm-5
This means that 3600d0230003414f30000203a7bc41a00 is mapped to two mpath links: dm-4 and dm-5.
As such, the following lines should be deleted from /etc/lvm/.cache:
/dev/dm-4 /dev/dm-5 /dev/mapper/3600d0230003414f30000203a7bc41a00 /dev/mapper/3600d0230003414f30000203a7bc41a00p1 /dev/mpath/3600d0230003414f30000203a7bc41a00 /dev/mpath/3600d0230003414f30000203a7bc41a00p1
In a HA-RAID two-system configuration, two SAS adapters are plugged in to two systems and connected to a shared SAS disk drawer. Setting the Preferred Dual Adapter State attribute to Primary on both SAS adapters can trigger a race condition and cause infinite failover between the two SAS adapters. This is because only one SAS adapter can be set to Primary.
To prevent this error, ensure that the Preferred Dual Adapter State of one SAS adapter is set to None if the other SAS adapter should be set to Primary.
If you need to use the hp_sw kernel module, install the updated device-mapper-multipath package.
You also need to properly configure the HP array to correctly use active/passive mode and recognize connections from a Linux machine. To do this, perform the following steps:
Use the show connections command to determine each connection's world wide port name (WWPN). Below is a sample output of show connections on an HP MSA1000 array with two connections:
Connection Name: <Unknown> Host WWNN = 200100E0-8B3C0A65 Host WWPN = 210100E0-8B3C0A65 Profile Name = Default Unit Offset = 0 Controller 2 Port 1 Status = Online Connection Name: <Unknown> Host WWNN = 200000E0-8B1C0A65 Host WWPN = 210000E0-8B1C0A65 Profile Name = Default Unit Offset = 0 Controller 1 Port 1 Status = Online
Configure each connection properly using the following command:
add connection
[connection name] WWPN=[WWPN ID] profile=Linux OFFSET=[unit offset]
Note that can be set arbitrarily.
[connection name]
Using the given example, the proper commands should be:
add connection foo-p2 WWPN=210000E0-8B1C0A65 profile=Linux OFFSET=0
add connection foo-p1 WWPN=210100E0-8B3C0A65 profile=Linux OFFSET=0
Run show connections again to verify that each connection is properly configured. As per the given example, the correct configuration should be:
Connection Name: foo-p2 Host WWNN = 200000E0-8B1C0A65 Host WWPN = 210000E0-8B1C0A65 Profile Name = Linux Unit Offset = 0 Controller 1 Port 1 Status = Online Connection Name: foo-p1 Host WWNN = 200100E0-8B3C0A65 Host WWPN = 210100E0-8B3C0A65 Profile Name = Linux Unit Offset = 0 Controller 2 Port 1 Status = Online
Red Hat discourages the use of quota on EXT3 file systems. This is because in some cases, doing so can cause a deadlock.
Testing has revealed that kjournald can sometimes block some EXT3-specific callouts that are used when quota is running. As such, Red Hat does not plan to fix this issue in Red Hat Enterprise Linux 4, as the modifications required would be too invasive.
Note that this issue is not present in Red Hat Enterprise Linux 5.
Hardware testing for the Mellanox MT25204 has revealed that an internal error occurs under certain high-load conditions. When the ib_mthca driver reports a catastrophic error on this hardware, it is usually related to an insufficient completion queue depth relative to the number of outstanding work requests generated by the user application.
Although the driver will reset the hardware and recover from such an event, all existing connections at the time of the error will be lost. This generally results in a segmentation fault in the user application. Further, if opensm is running at the time the error occurs, then you need to manually restart it in order to resume proper operation.
The Desktop Sharing connection icon displays its context menu when you double-click it, not when you right-click it. All other icons display their context menus when you right-click on them.