Before storage device can be removed (or unassigned) from server, it must first be removed from Linux. This is even more necessary if the server is running Oracle ASMLib, because if there are any removed or read-only storage devices present when running service oracleasm scandisks, the command will just hang and server load will start to increase (maximum I've seen was 3500).
Ubuntu is a very popular operating system (OS) in the cloud space but the Federal government has been reluctant to adopt Ubuntu, preferring to stick with Redhat as their Linux flavor of choice. As the Government moves toward the cloud it makes sense to me that Ubuntu would start to see some more play time. One of the big hurdles to this is the need to ensure that Ubuntu meets the Federal Information Security Management Act (more...)
Every DBA working with the Oracle database must have seen memory dumps in tracefiles. It is present in ORA-600 (internal error) ORA-7445 (operating system error), system state dumps, process state dumps and a lot of other dumps.
This is how it looks likes:
Dump of memory from 0x00007F06BF9A9E00 to 0x00007F06BF9ADE00 7F06BF9A9E00 0000C215 0000001F 00000CC1 0401FFFF [................] 7F06BF9A9E10 000032F3 00010003 00000002 442B0000 [.2............+D] 7F06BF9A9E20 2F415441 31323156 4F2F3230 4E494C4E [ATA/V12102/ONLIN] 7F06BF9A9E30 474F4C45 6F72672F 315F7075 (more...)
Thanks to Andy Colvin (@acolvin) and the Enkitec lab I have been able to get my hands on an ODA X4-2. And since that’s a lot quieter than turning on my own lab server, and also a lot faster I used the environment to test RAC One Node in 188.8.131.52.1. I recently had a question from a customer about the usefulness of the solution and what it brings to the HA (more...)
Oracle database operating system memory allocation management for PGA – part 4: Oracle 184.108.40.206 and AMM
This is the 4th post in a series of posts on PGA behaviour of Oracle. Earlier posts are: here (PGA limiting for Oracle 12), here (PGA limiting for Oracle 11.2) and the quiz on using PGA with AMM, into which this blogpost dives deeper.
As laid out in the quiz blogpost, I have a database with the following specifics:
-Oracle Linux x86_64 6u6.
-Oracle database 220.127.116.11 PSU 4
I’ve posted a new installation cookbook for using Oracle within a virtual machine running on Oracle VM. Surprisingly, I was unable to come up with a satisfactory method of accessing external storage that did not involve the use of Oracle ASMLib…
Filed under: Blog, Cookbooks, Database, Flash, Linux, Storage Tagged: cookbooks, database, oracle, oracle vm
Oracle database operating system memory allocation management for PGA – part 3: Oracle 18.104.22.168 and AMM: Quiz
Today a little wednesday fun: a quiz.
What do you think will happen in the following situation:
-Oracle Linux x86_64 6u6.
-Oracle database 22.214.171.124 PSU 4
-Oracle database (single instance) with the following parameter set: memory_target=1G. No other (more...)
This is the second part of a series of blogpost on Oracle database PGA usage. See the first part here. The first part described SGA and PGA usage, their distinction (SGA being static, PGA being variable), the problem (no limitation for PGA allocations outside of sort, hash and bitmap memory), a resolution for Oracle 12 (PGA_AGGREGATE_LIMIT), and some specifics about that (it doesn’t look like a very hard limit).
But this leaves out Oracle version (more...)
This post is about memory management on the operating system level of an Oracle database. The first question that might pop in your head is: isn’t this a solved problem? The answer is: yes, if you use Oracle’s AMM (Automatic Memory Management) feature, which let’s you set a limit for the Oracle datababase’s two main memory area’s: SGA and PGA. But in my opinion any serious, real life, usage of an Oracle database on Linux (more...)
In one of my old posts, I wrote a step by step guide to install Ops Center on Linux. I still get questions about installation, mostly about installing repository Database. So I have downloaded latest patch set version if anything has changed about installation, and decided to write tips and tricks to help Ops Center users. If you have read my previous blog, or you are already an Ops Center user, you may remember (more...)
I posted a fair amount of stuff on how Oracle is generating IOs, and especially large IOs, meaning more than one Oracle block, so > 8KB. This is typically what is happening when the Oracle database is executing a row source which does a full segment scan. Let’s start off with a quiz: what you think Oracle is the maximum IO size the Oracle engine is capable of requesting of the Operating System (so the (more...)
This is a quick post on using git on a server. I use my Synology NAS as a fileserver, but also as a git repository server. The default git package for Synology enables git usage on the command line, which means via ssh, or via web-DAV. Both require a logon to do anything with the repository. That is not very handy if you want to clone and pull from the repository. Of course there are (more...)
There has recently been a lot of news about the exploit revealed in the bash shell. While the fix is very quick to implement, there are a couple of tricks that are required to install this update on an Exadata environment. According to Oracle support note #1405320.1, Exadata storage server versions 11.2.3.x.x and 12.1.1.x.x are susceptible to the exploit. On a typical Oracle Enterprise Linux, a simple (more...)
Thank You @OracleAlchemist and @gokhanatil for good information about it.
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup0-U01LV 50G 52M 47G 1% /u01
[root@mytest01 ~]# fdisk -l (more...)
Oracle introduces centos2ol.sh script that can convert CentOS 5 and 6 systems to Oracle Linux. After that run "yum upgrade" again.
[root@test-centos ~]# uname -r
Most of the talk about Oracle’s release of 126.96.36.199 is about the InMemory feature, but more things have changed, for example some essential things about loggin in the Grid Infrastructure have changed. Normally in Oracle Grid Infrastructure logging for Grid components was done in $GI_HOME:
oracle@dm01db01(*gridinfra):/home/oracle> cd $ORACLE_HOME/log/`hostname -s`/ oracle@dm01db01(*gridinfra):/u01/app/188.8.131.52/grid/log/dm01db01>
There we have the main alert log for GI and several subdirectories for the GI binaries where they write (more...)
I’m sharing this in the hope of saving someone from an unwelcome surprise.
I recent upgraded an Exadata system from 184.108.40.206.1 to 220.127.116.11.1. Apart from what turns out to be a known bug that resulted in the patching of the InfiniBand switches “failing”, it all seemed to go without a snag. That’s until I decided to do some node failure testing…
Having forced a node (more...)
The following is a list of changes I noted during installation of Oracle Linux 7. I imagine the same will apply to Red Hat Enterprise Linux 7, but I haven’t verified that to be the case.
Setting the Hostname
I was accustomed to updating /etc/sysconfig/network with the hostname of my machine as documented here for Oracle Linux 7. I did this and was then surprised to find that my hostname was not picked up. On returning (more...)
There is a good article how to mount vmfs, but on debian i had to install the package otherosfs.
After i installed this (more...)