Exadata 11.2.3.2.1 NFS Issues – Ksplice Support for Exadata?

By | March 7, 2013

When the 11.2.3.2.1 release of the Exadata Storage Server software was released, I was a little excited.  There were numerous oneoff patches for the previous release, 11.2.3.2.0, which was the first version to support the Exadata X3, writeback flashcache, run UEK on the X#-2 systems, etc.  With that many large changes introduced in one version, it was likely to see some bugs in the .0 release.  Fortunately, Oracle was quick to fix many of those issues, but it resulted in several separate patches to update the cellsrv software.

I was working with a colleague last week where we ready to apply this patch to a customer’s Exadata system.  Everything went off without a hitch – upgrading from 11.2.2.4.2 straight to 11.2.3.2.1.  We even applied the patch to the customer’s quarter rack in rolling mode, which took under 6 hours to complete.  After everything was back up and running, we took an archive log backup using RMAN.  For this customer, we back everything up to NFS because it won’t fit within the FRA, and they don’t want to leave backups inside the production system.  We were greeted with a strange error when we tried to kick off the backup job in RMAN:

RMAN> run {
2>   ALLOCATE CHANNEL DISK1 DEVICE TYPE DISK;
3>   BACKUP DATABASE FORMAT '/mnt/nfs/actest_%U';
4>   RELEASE CHANNEL DISK1;
5> }
 
using target database control file instead of recovery catalog
allocated channel: DISK1
channel DISK1: SID=397 instance=ACTEST1 device type=DISK
 
Starting backup at 13-02-28 21:38
channel DISK1: starting full datafile backup set
channel DISK1: specifying datafile(s) in backup set
input datafile file number=00007 name=+DATA/actest/datafile/tanel_bigfile.325.808412931
input datafile file number=00006 name=+DATA/actest/datafile/ts_data.380.779860027
input datafile file number=00001 name=+DATA/actest/datafile/system.367.779029515
input datafile file number=00002 name=+DATA/actest/datafile/sysaux.368.779029555
input datafile file number=00003 name=+DATA/actest/datafile/undotbs1.369.779029595
input datafile file number=00004 name=+DATA/actest/datafile/undotbs2.371.779029649
input datafile file number=00005 name=+DATA/actest/datafile/users.372.779029687
channel DISK1: starting piece 1 at 13-02-28 21:38
released channel: DISK1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of backup command on DISK1 channel at 02/28/2013 21:38:37
ORA-19504: failed to create file "/mnt/nfs/actest_1jo34pas_1_1"
ORA-27044: unable to write the header block of file
Linux-x86_64 Error: 12: Cannot allocate memory
Additional information: 3

It didn’t matter what we were trying to back up, just that it was going to NFS.  This backup job had worked fine prior to the patch (we took a backup immediately preceding the maintenance window), but we had applied both a database bundle patch (this database was 11.2.0.2) and the latest storage server patch (11.2.3.2.1), which updates the Linux OS to OEL 5.8, as well as introduces the Oracle Unbreakable Enterprise Kernel into the mix.

We checked the mount options to make sure that everything was ok, and saw that it was:

[enkdb01:oracle:ACTEST1] /u01/app/oracle/product/11.2.0.3/dbhome_2/rdbms/lib 
> mount | grep "/mnt/nfs"
192.168.12.22:/export/nfs on /mnt/nfs type nfs (rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,nfsvers=3,timeo=600,actimeo=0,addr=192.168.12.22)

After poking around a bit, we opened a service request, which was answered pretty quickly by Oracle support.  It turns out that there is a known bug with the NFS driver included in the version of the UEK packaged with 11.2.3.2.1. Oracle provided 3 possible fixes, which I’ll detail below. The fixes were:


Enable direct NFS


First, I’ll cover enabling direct NFS.  I actually have a blog post in the works, but to give you a quick once-over on it, here goes.  Direct NFS is a custom-built NFS driver that does not interfere with the kernel’s NFS driver.  Any operations that go through the database (RMAN, data pump, etc) will use this special driver that is optimized for database operations.  Processes that utilize direct NFS operate in user space (like FUSE), which has less overhead than kernel space.  Because direct NFS does not use the bad kernel NFS driver for backup operations, the bug is negated.  It goes without saying that if your databases are interacting with NFS, you should use direct NFS.  There is no penalty for doing so, and it’s really easy to do.  Shut down your database instance, and relink for direct NFS:

[enkdb01:oracle:ACTEST1] /home/oracle
>  cd $ORACLE_HOME/rdbms/lib
[enkdb01:oracle:ACTEST1] /u01/app/oracle/product/11.2.0.3/dbhome_2/rdbms/lib 
>  make -f ins_rdbms.mk dnfs_on
rm -f /u01/app/oracle/product/11.2.0.3/dbhome_2/lib/libodm11.so; cp /u01/app/oracle/product/11.2.0.3/dbhome_2/lib/libnfsodm11.so /u01/app/oracle/product/11.2.0.3/dbhome_2/lib/libodm11.so

That’s it.  If you see the following line in your alert log on instance startup, you’re on your way:

Oracle instance running with ODM: Oracle Direct NFS ODM Library Version 3.0

Once you start to access the NFS devices, you can query v$dnfs_servers to ensure that the database is using direct NFS.

SYS:ACTEST1> select * from v$dnfs_servers;
 
         ID        SVRNAME        DIRNAME     MNTPORT     NFSPORT       WTMAX       RTMAX
----------- -------------- -------------- ----------- ----------- ----------- -----------
          1  192.168.12.22    /export/nfs         939        2049           0           0


Switch to non-UEK


The next option provided by Oracle support was to switch from the Unbreakable Enterprise Kernel included with 11.2.3.2.1 to the RedHat compatible kernel.  To do this, follow the instructions in the readme for the patch (patch #14522699).

First, remove the problematic UEK packages:

[enkdb01:root] /root 
> yum remove exadata-sun-computenode kernel-uek-devel kernel-uek-debuginfo kernel-uek-doc kernel-uek-debuginfo-common kernel-uek-headers
Loaded plugins: security
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package exadata-sun-computenode.x86_64 0:11.2.3.2.1.130109-1 set to be erased
---> Package kernel-uek-debuginfo.x86_64 0:2.6.32-400.11.1.el5uek set to be erased
---> Package kernel-uek-debuginfo-common.x86_64 0:2.6.32-400.11.1.el5uek set to be erased
---> Package kernel-uek-devel.x86_64 0:2.6.32-400.11.1.el5uek set to be erased
---> Package kernel-uek-doc.noarch 0:2.6.32-400.11.1.el5uek set to be erased
---> Package kernel-uek-headers.x86_64 0:2.6.32-400.11.1.el5uek set to be erased
--> Processing Dependency: kernel-headers for package: glibc-headers
--> Processing Dependency: kernel-headers >= 2.2.1 for package: glibc-headers
--> Running transaction check
---> Package glibc-headers.x86_64 0:2.5-81.el5_8.7 set to be erased
--> Processing Dependency: glibc-headers for package: glibc-devel
--> Processing Dependency: glibc-headers = 2.5-81.el5_8.7 for package: glibc-devel
--> Processing Dependency: glibc-headers for package: glibc-devel
--> Processing Dependency: glibc-headers = 2.5-81.el5_8.7 for package: glibc-devel
--> Running transaction check
---> Package glibc-devel.i386 0:2.5-81.el5_8.7 set to be erased
--> Processing Dependency: glibc-devel >= 2.2.90-12 for package: gcc
--> Processing Dependency: glibc-devel >= 2.2.90-12 for package: compat-gcc-34
---> Package glibc-devel.x86_64 0:2.5-81.el5_8.7 set to be erased
--> Running transaction check
---> Package compat-gcc-34.x86_64 0:3.4.6-4 set to be erased
--> Processing Dependency: compat-gcc-34 = 3.4.6-4 for package: compat-gcc-34-c++
---> Package gcc.x86_64 0:4.1.2-52.el5_8.1 set to be erased
--> Processing Dependency: gcc = 4.1.2-52.el5_8.1 for package: gcc-c++
--> Running transaction check
---> Package compat-gcc-34-c++.x86_64 0:3.4.6-4 set to be erased
---> Package gcc-c++.x86_64 0:4.1.2-52.el5_8.1 set to be erased
--> Finished Dependency Resolution
 
Dependencies Resolved
 
========================================================================================================================================================
 Package                                        Arch                      Version                                    Repository                    Size
========================================================================================================================================================
Removing:
 exadata-sun-computenode                        x86_64                    11.2.3.2.1.130109-1                        installed                     95 k
 kernel-uek-debuginfo                           x86_64                    2.6.32-400.11.1.el5uek                     installed                    1.0 G
 kernel-uek-debuginfo-common                    x86_64                    2.6.32-400.11.1.el5uek                     installed                    163 M
 kernel-uek-devel                               x86_64                    2.6.32-400.11.1.el5uek                     installed                     45 M
 kernel-uek-doc                                 noarch                    2.6.32-400.11.1.el5uek                     installed                     33 M
 kernel-uek-headers                             x86_64                    2.6.32-400.11.1.el5uek                     installed                    2.2 M
Removing for dependencies:
 compat-gcc-34                                  x86_64                    3.4.6-4                                    installed                     12 M
 compat-gcc-34-c++                              x86_64                    3.4.6-4                                    installed                     84 M
 gcc                                            x86_64                    4.1.2-52.el5_8.1                           installed                    9.9 M
 gcc-c++                                        x86_64                    4.1.2-52.el5_8.1                           installed                    7.5 M
 glibc-devel                                    i386                      2.5-81.el5_8.7                             installed                    4.9 M
 glibc-devel                                    x86_64                    2.5-81.el5_8.7                             installed                    7.0 M
 glibc-headers                                  x86_64                    2.5-81.el5_8.7                             installed                    1.9 M
 
Transaction Summary
========================================================================================================================================================
Remove       13 Package(s)
Reinstall     0 Package(s)
Downgrade     0 Package(s)
 
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Erasing        : kernel-uek-debuginfo                                                                                                            1/13 
  Erasing        : kernel-uek-debuginfo-common                                                                                                     2/13 
  Erasing        : gcc                                                                                                                             3/13 
  Erasing        : glibc-headers                                                                                                                   4/13 
  Erasing        : compat-gcc-34                                                                                                                   5/13 
  Erasing        : glibc-devel                                                                                                                     6/13 
  Erasing        : glibc-devel                                                                                                                     7/13 
  Erasing        : compat-gcc-34-c++                                                                                                               8/13 
  Erasing        : kernel-uek-headers                                                                                                              9/13 
  Erasing        : gcc-c++                                                                                                                        10/13 
  Erasing        : kernel-uek-devel                                                                                                               11/13 
  Erasing        : exadata-sun-computenode                                                                                                        12/13 
  Erasing        : kernel-uek-doc                                                                                                                 13/13 
 
Removed:
  exadata-sun-computenode.x86_64 0:11.2.3.2.1.130109-1                           kernel-uek-debuginfo.x86_64 0:2.6.32-400.11.1.el5uek                   
  kernel-uek-debuginfo-common.x86_64 0:2.6.32-400.11.1.el5uek                    kernel-uek-devel.x86_64 0:2.6.32-400.11.1.el5uek                       
  kernel-uek-doc.noarch 0:2.6.32-400.11.1.el5uek                                 kernel-uek-headers.x86_64 0:2.6.32-400.11.1.el5uek                     
 
Dependency Removed:
  compat-gcc-34.x86_64 0:3.4.6-4      compat-gcc-34-c++.x86_64 0:3.4.6-4    gcc.x86_64 0:4.1.2-52.el5_8.1           gcc-c++.x86_64 0:4.1.2-52.el5_8.1  
  glibc-devel.i386 0:2.5-81.el5_8.7   glibc-devel.x86_64 0:2.5-81.el5_8.7   glibc-headers.x86_64 0:2.5-81.el5_8.7  
 
Complete!

Next, modify the exclude line in /etc/yum.conf to include kernel-uek-headers

exclude=up2date kernel-uek-headers

Stop and disable CRS on the node

[enkdb01:root] /root 
> crsctl stop crs
[enkdb01:root] /root 
> crsctl disable crs
CRS-4621: Oracle High Availability Services autostart is disabled.

Install the exadata-sun-computenode-non-uek package from the yum repository.

[enkdb01:root] /root 
> yum --enablerepo=exadata_dbserver_11.2.3.2.1_x86_64_base install exadata-sun-computenode-non-uek
Loaded plugins: security
exadata_dbserver_11.2.3.2.1_x86_64_base                                                                                          | 1.9 kB     00:00     
Excluding Packages in global exclude list
Finished
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package exadata-sun-computenode-non-uek.x86_64 0:11.2.3.2.1.130109-1 set to be updated
exadata_dbserver_11.2.3.2.1_x86_64_base/filelists_db                                                                             | 680 kB     00:00     
--> Processing Dependency: gcc = 4.1.1-52.el5_8 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: glibc-kernheaders = 3.0-46 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: kernel-headers = 2.6.18-308.24.1.0.1.el5 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: gcc = 4.1.2-52.el5_8.1 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: ofa-2.6.18-308.24.1.0.1.el5 = 1.5.1-4.0.58 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: glibc-devel = 2.5-81.el5_8.7 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: glibc-headers = 2.5-81.el5_8.7 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: gcc-c++ = 4.1.1-52.el5_8 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: gcc-c++ = 4.1.2-52.el5_8.1 for package: exadata-sun-computenode-non-uek
--> Processing Dependency: megaraid_sas-2.6.18-308.24.1.0.1.el5 = v00.00.06.12-ORCL.2 for package: exadata-sun-computenode-non-uek
--> Running transaction check
---> Package gcc.x86_64 0:4.1.2-52.el5_8.1 set to be updated
---> Package gcc-c++.x86_64 0:4.1.2-52.el5_8.1 set to be updated
---> Package glibc-devel.x86_64 0:2.5-81.el5_8.7 set to be updated
---> Package glibc-headers.x86_64 0:2.5-81.el5_8.7 set to be updated
---> Package kernel-headers.x86_64 0:2.6.18-308.24.1.0.1.el5 set to be updated
---> Package megaraid_sas-2.6.18-308.24.1.0.1.el5.x86_64 0:v00.00.06.12-ORCL.2 set to be updated
---> Package ofa-2.6.18-308.24.1.0.1.el5.x86_64 0:1.5.1-4.0.58 set to be updated
--> Finished Dependency Resolution
 
Dependencies Resolved
 
========================================================================================================================================================
 Package                                       Arch            Version                           Repository                                        Size
========================================================================================================================================================
Installing:
 exadata-sun-computenode-non-uek               x86_64          11.2.3.2.1.130109-1               exadata_dbserver_11.2.3.2.1_x86_64_base           47 k
Installing for dependencies:
 gcc                                           x86_64          4.1.2-52.el5_8.1                  exadata_dbserver_11.2.3.2.1_x86_64_base          5.3 M
 gcc-c++                                       x86_64          4.1.2-52.el5_8.1                  exadata_dbserver_11.2.3.2.1_x86_64_base          3.8 M
 glibc-devel                                   x86_64          2.5-81.el5_8.7                    exadata_dbserver_11.2.3.2.1_x86_64_base          2.4 M
 glibc-headers                                 x86_64          2.5-81.el5_8.7                    exadata_dbserver_11.2.3.2.1_x86_64_base          597 k
 kernel-headers                                x86_64          2.6.18-308.24.1.0.1.el5           exadata_dbserver_11.2.3.2.1_x86_64_base          1.4 M
 megaraid_sas-2.6.18-308.24.1.0.1.el5          x86_64          v00.00.06.12-ORCL.2               exadata_dbserver_11.2.3.2.1_x86_64_base          287 k
 ofa-2.6.18-308.24.1.0.1.el5                   x86_64          1.5.1-4.0.58                      exadata_dbserver_11.2.3.2.1_x86_64_base          846 k
 
Transaction Summary
========================================================================================================================================================
Install       8 Package(s)
Upgrade       0 Package(s)
 
Total download size: 15 M
Is this ok [y/N]: y
Downloading Packages:
--------------------------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                                   4.5 GB/s |  15 MB     00:00     
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing     : kernel-headers                                                                                                                   1/8 
  Installing     : glibc-headers                                                                                                                    2/8 
  Installing     : glibc-devel                                                                                                                      3/8 
  Installing     : ofa-2.6.18-308.24.1.0.1.el5                                                                                                      4/8 
  Installing     : megaraid_sas-2.6.18-308.24.1.0.1.el5                                                                                             5/8 
Current initrd saved in /boot/initrd-2.6.18-308.24.1.0.1.el5.img.bak.066-2200.11.2.3.2.1.130109
initrd image created: /boot/initrd-2.6.18-308.24.1.0.1.el5.img
  Installing     : gcc                                                                                                                              6/8 
  Installing     : gcc-c++                                                                                                                          7/8 
  Installing     : exadata-sun-computenode-non-uek                                                                                                  8/8 
 
Installed:
  exadata-sun-computenode-non-uek.x86_64 0:11.2.3.2.1.130109-1                                                                                              
 
Dependency Installed:
  gcc.x86_64 0:4.1.2-52.el5_8.1                                        gcc-c++.x86_64 0:4.1.2-52.el5_8.1                                                   
  glibc-devel.x86_64 0:2.5-81.el5_8.7                                  glibc-headers.x86_64 0:2.5-81.el5_8.7                                               
  kernel-headers.x86_64 0:2.6.18-308.24.1.0.1.el5                      megaraid_sas-2.6.18-308.24.1.0.1.el5.x86_64 0:v00.00.06.12-ORCL.2                   
  ofa-2.6.18-308.24.1.0.1.el5.x86_64 0:1.5.1-4.0.58                   
 
Complete!
 
[enkdb01:root] /root 
> 
Remote broadcast message (Thu Mar  7 22:00:43 2013):
 
Exadata post install steps started.
It may take up to 2 minutes.
The db node will be rebooted upon successful completion.

This will cause the compute node to reboot.  When it has come up, check to make sure that the server booted to the non-UEK version of the kernel:

[enkdb01:root] /root 
> uname -a
Linux enkdb01.enkitec.com 2.6.18-308.24.1.0.1.el5 #1 SMP Tue Dec 4 16:00:29 PST 2012 x86_64 x86_64 x86_64 GNU/Linux

Remove the unused UEK RPMs, and install the glibc RPM.

[enkdb01:root] /root 
> yum remove kernel-uek kernel-uek-firmware
Loaded plugins: security
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package kernel-uek.x86_64 0:2.6.32-300.7.2.el5uek set to be erased
--> Processing Dependency: kernel-uek = 2.6.32-300.7.2.el5uek for package: megaraid_sas-2.6.32-300.7.2.el5uek
--> Processing Dependency: kernel-uek = 2.6.32-300.7.2.el5uek for package: ofa-2.6.32-300.7.2.el5uek
---> Package kernel-uek.x86_64 0:2.6.32-300.7.3.el5uek set to be erased
--> Processing Dependency: kernel-uek = 2.6.32-300.7.3.el5uek for package: ofa-2.6.32-300.7.3.el5uek
--> Processing Dependency: kernel-uek = 2.6.32-300.7.3.el5uek for package: megaraid_sas-2.6.32-300.7.3.el5uek
---> Package kernel-uek.x86_64 0:2.6.32-400.1.1.el5uek set to be erased
--> Processing Dependency: kernel-uek = 2.6.32-400.1.1.el5uek for package: ofa-2.6.32-400.1.1.el5uek
---> Package kernel-uek.x86_64 0:2.6.32-400.11.1.el5uek set to be erased
--> Processing Dependency: kernel-uek = 2.6.32-400.11.1.el5uek for package: ofa-2.6.32-400.11.1.el5uek
---> Package kernel-uek-firmware.noarch 0:2.6.32-400.11.1.el5uek set to be erased
--> Running transaction check
---> Package megaraid_sas-2.6.32-300.7.2.el5uek.x86_64 0:v00.00.06.12-ORCL.2 set to be erased
---> Package megaraid_sas-2.6.32-300.7.3.el5uek.x86_64 0:v00.00.06.12-ORCL.2 set to be erased
---> Package ofa-2.6.32-300.7.2.el5uek.x86_64 0:1.5.1-4.0.58 set to be erased
---> Package ofa-2.6.32-300.7.3.el5uek.x86_64 0:1.5.1-4.0.58 set to be erased
---> Package ofa-2.6.32-400.1.1.el5uek.x86_64 0:1.5.1-4.0.58 set to be erased
---> Package ofa-2.6.32-400.11.1.el5uek.x86_64 0:1.5.1-4.0.58 set to be erased
--> Finished Dependency Resolution
 
Dependencies Resolved
 
==========================================================================================================================================================================
 Package                                                  Arch                         Version                                      Repository                       Size
==========================================================================================================================================================================
Removing:
 kernel-uek                                               x86_64                       2.6.32-300.7.2.el5uek                        installed                        81 M
 kernel-uek                                               x86_64                       2.6.32-300.7.3.el5uek                        installed                        81 M
 kernel-uek                                               x86_64                       2.6.32-400.1.1.el5uek                        installed                        82 M
 kernel-uek                                               x86_64                       2.6.32-400.11.1.el5uek                       installed                        82 M
 kernel-uek-firmware                                      noarch                       2.6.32-400.11.1.el5uek                       installed                       5.3 M
Removing for dependencies:
 megaraid_sas-2.6.32-300.7.2.el5uek                       x86_64                       v00.00.06.12-ORCL.2                          installed                       1.1 M
 megaraid_sas-2.6.32-300.7.3.el5uek                       x86_64                       v00.00.06.12-ORCL.2                          installed                       1.1 M
 ofa-2.6.32-300.7.2.el5uek                                x86_64                       1.5.1-4.0.58                                 installed                       3.4 M
 ofa-2.6.32-300.7.3.el5uek                                x86_64                       1.5.1-4.0.58                                 installed                       3.4 M
 ofa-2.6.32-400.1.1.el5uek                                x86_64                       1.5.1-4.0.58                                 installed                       3.4 M
 ofa-2.6.32-400.11.1.el5uek                               x86_64                       1.5.1-4.0.58                                 installed                       3.4 M
 
Transaction Summary
==========================================================================================================================================================================
Remove       11 Package(s)
Reinstall     0 Package(s)
Downgrade     0 Package(s)
 
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Erasing        : kernel-uek                                                                                                                                        1/11 
  Erasing        : ofa-2.6.32-400.1.1.el5uek                                                                                                                         2/11 
  Erasing        : kernel-uek                                                                                                                                        3/11 
  Erasing        : ofa-2.6.32-300.7.2.el5uek                                                                                                                         4/11 
Megaraid path valid. Proceeding.
  Erasing        : megaraid_sas-2.6.32-300.7.3.el5uek                                                                                                                5/11 
  Erasing        : ofa-2.6.32-300.7.3.el5uek                                                                                                                         6/11 
  Erasing        : ofa-2.6.32-400.11.1.el5uek                                                                                                                        7/11 
  Erasing        : kernel-uek                                                                                                                                        8/11 
  Erasing        : kernel-uek-firmware                                                                                                                               9/11 
Megaraid path valid. Proceeding.
Warning. /lib/modules/2.6.32-300.7.2.el5uek/kernel/drivers/scsi/megaraid/megaraid_sas.ko does not match file from the uninstalling rpm
Warning. Leave megaraid_sas driver as is
+ exit 0
  Erasing        : megaraid_sas-2.6.32-300.7.2.el5uek                                                                                                               10/11 
  Erasing        : kernel-uek                                                                                                                                       11/11 
 
Removed:
  kernel-uek.x86_64 0:2.6.32-300.7.2.el5uek            kernel-uek.x86_64 0:2.6.32-300.7.3.el5uek                     kernel-uek.x86_64 0:2.6.32-400.1.1.el5uek          
  kernel-uek.x86_64 0:2.6.32-400.11.1.el5uek           kernel-uek-firmware.noarch 0:2.6.32-400.11.1.el5uek          
 
Dependency Removed:
  megaraid_sas-2.6.32-300.7.2.el5uek.x86_64 0:v00.00.06.12-ORCL.2                     megaraid_sas-2.6.32-300.7.3.el5uek.x86_64 0:v00.00.06.12-ORCL.2                    
  ofa-2.6.32-300.7.2.el5uek.x86_64 0:1.5.1-4.0.58                                     ofa-2.6.32-300.7.3.el5uek.x86_64 0:1.5.1-4.0.58                                    
  ofa-2.6.32-400.1.1.el5uek.x86_64 0:1.5.1-4.0.58                                     ofa-2.6.32-400.11.1.el5uek.x86_64 0:1.5.1-4.0.58                                   
 
Complete!
 
[enkdb01:root] /root 
> yum --enablerepo=exadata_dbserver_11.2.3.2.1_x86_64_base install glibc-devel.i386
Loaded plugins: security
Excluding Packages in global exclude list
Finished
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package glibc-devel.i386 0:2.5-81.el5_8.7 set to be updated
--> Finished Dependency Resolution
 
Dependencies Resolved
 
==========================================================================================================================================================================
 Package                           Arch                       Version                                 Repository                                                     Size
==========================================================================================================================================================================
Installing:
 glibc-devel                       i386                       2.5-81.el5_8.7                          exadata_dbserver_11.2.3.2.1_x86_64_base                       2.1 M
 
Transaction Summary
==========================================================================================================================================================================
Install       1 Package(s)
Upgrade       0 Package(s)
 
Total download size: 2.1 M
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing     : glibc-devel                                                                                                                                        1/1 
 
Installed:
  glibc-devel.i386 0:2.5-81.el5_8.7                                                                                                                                       
 
Complete!

Finally, relink the Oracle homes, restart CRS, and try backing up your database.

[enkdb01:root] /root 
> crsctl enable crs
CRS-4622: Oracle High Availability Services autostart is enabled.
 
[enkdb01:root] /root 
> crsctl start crs
CRS-4123: Oracle High Availability Services has been started.


Ksplice on the UEK


The last option is the most interesting, in my opinion – applying an online kernel patch using ksplice.  If you’re not familiar with ksplice, it is a magical little piece of software acquired by Oracle which allows administrators to apply kernel patches to the kernel running in memory, eliminating the need for a reboot (generally).  Because ksplice isn’t fully supported on Exadata, we have a few limitations on what can be done, but this is an interesting glimpse into what may be coming in future releases.  This patch (provided by Oracle Support) is a single ksplice patch for this bug.  To install, unzip the patch, copy the patch file to the uptrack directory, and apply the patch.  All of the following must be done as root.

First, make sure that there aren’t any patches installed

[enkdb01:root] /tmp/ksplice_patch/uptrack
> ./ksplice-view
 
[enkdb01:root] /tmp/ksplice_patch/uptrack
>

Next, apply the patch – this takes about 3 seconds to apply:

[enkdb01:root] /tmp/ksplice_patch/uptrack
> ./ksplice-apply ksplice-9j3o3021.tar.gz
Done!

Check that the patch has applied successfully

[enkdb01:root] /tmp/ksplice_patch/uptrack
> ./ksplice-view
9j3o3021: Ksplice test suite: oracle-uek5-2.6.32-400.11.1.el5uek-amd64

That’s all there is to it.  This will need to be applied on both nodes, and since it’s not a full installation of ksplice, the patch will have to be reapplied upon each reboot of the compute node.  If you really want to, you could create a script to apply the patch when the server boots up.  On full installations of ksplice, the kernel will be “respliced” upon each reboot.

 

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11 thoughts on “Exadata 11.2.3.2.1 NFS Issues – Ksplice Support for Exadata?

  1. jason arneil

    Hi Andy,

    Really helpful blog, I don’t think you are going to be alone in hitting this one!

    I take it the uptrack command comes with the patch, rather than native on the Exadata? Did you have to get the patch specially from Oracle support, or is it generally available? i.e. do you have a patch number?

    cheers,

    jason.

    Reply
    1. Andy Colvin Post author

      Yes, the uptrack command is not the standard ksplice uptrack command. It is included in the patch provided by Oracle. Unfortunately, there’s no full support of ksplice yet.

      Reply
  2. freek

    I installed the exact same patch last week. The ksplice patching went indeed really easy.
    I have also been looking into using our local yum repo server for the ksplice offline client, but had to abandon it due a lack of disk space (and time).

    Have you done some investigations into it?

    Also I have been investigating backup performance and it seems that without dnfs you really need to enable async io via the filesystemio_options parameter to get some real performance (but had to hand the environment back, before I could do some formal camparison testing).
    Dnfs is using async without having to specify it in the filesystemio_options parameter.

    Reply
    1. Andy Colvin Post author

      I’m just starting to play around with ksplice. I’ve seen some demos of it lately, and it’s pretty cool.

      Reply
  3. Klaas-Jan Jongsma

    Nice find, i just ran into the same issue this week at a customers site. I always thought that you still needed a seperate license for using ksplice?

    Reply
  4. Renan Medeiros

    There is a patch , see note ID 1532488.1 on metalink.
    Solution

    1. Install patch 16432033: EXADATA COMPUTE NODE 11.2.3.2.1 BASE REPOSITORY ISO WITH FIXES

    This repository ISO image contains only the Oracle Exadata release 11.2 Latest channel which includes 11.2.3.2.1 Base channel plus fixes for bugs 16263472, 16046497 and 15956690. If RPMs from additional channels are required, then they must be obtained via other methods. This patch supercedes the contents of the ISO contained in patch 15991297. Customers already on 11.2.3.2.1 should consider applying this updated patch. Refer to the patch README for more information.

    Reply
    1. Andy Colvin Post author

      Yes, Oracle has released a newer ISO file. The version of the software is the same, with the exception of the timestamp at the end. Here’s info from a server with the older 11.2.3.2.1 patch installed:

      Kernel version: 2.6.32-400.11.1.el5uek #1 SMP Thu Nov 22 03:29:09 PST 2012 x86_64
      Image version: 11.2.3.2.1.130109
      Image activated: 2013-02-20 21:48:21 -0800
      Image status: success
      System partition on device: /dev/mapper/VGExaDb-LVDbSys1

      Here’s info from a server with the later patch:

      Kernel version: 2.6.32-400.21.1.el5uek #1 SMP Wed Feb 20 01:35:01 PST 2013 x86_64
      Image version: 11.2.3.2.1.130302
      Image activated: 2013-05-06 13:11:32 -0600
      Image status: success
      System partition on device: /dev/mapper/VGExaDb-LVDbSys1

      Note the difference between the kernel versions (2.6.32-400.11.1 vs 2.6.32.400.21.1) and the timestamp on the image version (11.2.3.2.1.130109 vs 11.2.3.2.1.130302)

      Reply
  5. Ry

    Thanks. I already forgot about the ksplice patch since we applied it a year ago after searching thru google I found your post and remembered we did the ksplice patch long ago. Thans again.

    Reply
  6. Pingback: Kdump to NFS Broken in UEK | NASMART

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