Why Oracle 23ai from Exadata? With Oracle Database 23ai being postponed to a later date (“tba”) in November 2024, and many people not being part of the Oracle Beta Program, it might be useful to install a regular database 23ai (not the Developer Free Edition), but of course for testing purposes only! This has to […]
Category: Linux / Unix
My experiences with the penguin and his colleagues.
Pictures and Download DOAG 2024 talks
Die largest Oracle Conference in Germany is DOAG Conference + Exhibition in November. It’s always the hotspot for the whois-who in the Oracle landscape. I had the chance to present three talks one of them with Axel vom Stein, Oracle ACE Pro, working with our valued customer BSS Bohnenberg, Solingen. Talks at DOAG 2024 Three talks, all […]
Oracle Linux 8/RHEL8: Lock User After Failed Login Attempts with Faillock
Many security audits and checklists like the ones supplied by CIS or DISA STIG require locking user accounts after a number of unsuccessful login attempts. In Linux, this is usually achieved by using faillock / pam_faillock.so. Using PAM PAM (Pluggable Authentication Modules) is the flexible framework in modern Linux to customize the authentication and login […]
Database 19c Certified for Oracle Linux 9 – Preinstall Package Available
Oracle Database 19c is certified for Oracle Linux 9 now (minimum requirement RU19.19). The Oracle Database preinstall package in its initial version is also available on the public Oracle yum server, in the AppStream Repo. https://yum.oracle.com/repo/OracleLinux/OL9/appstream/x86_64/getPackage/oracle-database-preinstall-19c-1.0-1.el9.x86_64.rpm […]
Oracle gridSetup.sh Fails with Error Code 255
Bash Error 255 Sometimes you have to apply a RU when launching Oracle 19c gridSetup.sh to install Oracle Grid Infrastructure or Oracle restart. For example when you install it in its vanilla 19.3 version on Oracle Linux 8. OL8 did not exist when they made 19.3, so some of its specials (like verifying group/user existence) […]
Create Oracle Data Guard Standby with DBCA
Demands of Automation You can easily create an Oracle Data Guard Standby Database with the Database Configuration Assistant DBCA. That’s especially interesting if you have automation at work, and are not keen on configuring stuff all over the place. This is available in version 19c upwards. DBCA uses RMAN DUPLICATE FOR STANDBY with an auxiliary […]
ORATOP in Oracle 19c
In 19c , the useful utility “oratop” is shipped with the Oracle Home installation. It was linked to the recent libaries, and its command line syntax changed. Error This leads to errors when calling one of the old “download” binaries like oratop12c-64.bin in a 19c environment: /home/oracle/bin/oratop12c-64.bin: error while loading shared libraries: libclntshcore.so.12.1: cannot open […]
Oracle on SLES12 SP2 – Avoiding Cgroup Task Limit
Once upon a time, there was an Oracle RAC cluster 12.2.0.1 on SUSE Linux Enterprise Server (SLES) 12 SP2, that did not do well. Its database and ASM instances used to fail with: ORA-27300: OS system dependent operation:fork failed with status: 11 ORA-27301: OS failure message: Resource temporarily unavailable ORA-27302: failure occurred at: skgpspawn3 Of […]
Oracle 12.2 sysctl.conf Default Preinstall Settings
This are the currently active settings, the oracle-database-server-12cR2-preinstall.rpm delivers on Oracle Linux 7. Maybe it’s useful for you when setting up Oracle 12.2 on SUSE / SLES where you are on your own. Maybe you also want to add Huge Pages: # Performing Databases Huge Page Settings # for SGA size 200GB and huge page […]
Oracle RAC 12.2 on SLES12 – How to disable Hardware Lock Elision Support
The Problem In the last week, I had to set up an Oracle RAC (and thus, the Clusterware) version 12.2.0.1 on SuSE Linux Enterprise Server 12 SP2 (SLES12 Sp2). The gridSetup.sh failed latest in root.sh of the first node with a kinda non-intuitive error: CRS-5804: Communication error with agent process CRS-4000: Command Start failed, or […]
Oracle RAC 12.2 High Load on CPU from gdb when Node Missing
Recently I had to battle a new issue with the quite-new Oracle Database RAC Version 12.2.0.1 on Linux x86_64. The idea of RAC is, to compensate the loss of a node or service by restarting services on other nodes. But in my case, when one node in a two-node-Cluster was down (or the crs stack […]
Oracle Enterprise Linux 7: How to stop bash tab completion from escaping the dollar $
Did you ever wonder why bash in Oracle Linux, Red Hat Enterprise Linux and other recent Linuxes escapes the dollar sign ($) when completing paths with the tabulator (tab) key like that: [oracle@oratest01 ~]$ (KLM12102) ls -l \$ORACLE_BASE/diag Answer In bash >= 4.2.29 you have a “direxpand” option, which is NOT set by default. The […]
How to disable Oracle ACFS drivers / registry resource
Sometimes an installed ACFS can cause trouble, especially if we don’t or can’t use it (e.g. when not using an UEK Linux kernel, like with SuSE Linux Enterprise Server SLES). There’s lots of documentation how to create and maintain ACFS file systems, but how to get rid of ACFS at all wasn’t so easy to […]
Chemnitzer Linux Tage 2015
Last weekend, I had the chance to attend the Linux Days Chemnitz. It’s an annual meeting of the German Linux family with roundabout 2,500 attendees and a FANTASTIC atmosphere. It was two days of hearing tech talks, enjoying rich nerd content and talkin’ shop. […]
New German Linux Forum (forum.linux-talk.de)
In the last weeks, some folks were busy to build a new German Linux Forum “forum.linux-talk.de”, since the predecessor was systematically ruined by the commercial owners. Especially Jean (wdp) and Hendrik (Nilpferd) invested much time and money into building the new environment. So the new forum is completely free of ads and commercials, and the […]
Oracle on Linux: How to hide your password when using a wrapper script
Sometimes, a DBA has to write an externally called wrapper script for various Oracle-supplied commands accepting password inputs. A prominent and simple example is SQL*plus (sqlplus). The Problem The process list shows all parameters of a command that’s currently executed. wrapper1.sh Accepts all connection infos on the command line: #!/bin/bash cmdstring=”sqlplus ${1}/${2}@${3}” echo “Executed command: […]
Oracle Clusterware root.sh issue: USM driver install actions failed (oracleoks.ko)
As I already said in my last post about “Can’t install ohasd service“, setting up Oracle Clusterware 11.2.0.4 on SuSE Linux Enterprise Server (SLES) SP2 should work flawlessly, but sometimes it does not. 🙂 This time, it was about the USM drivers. USM driver install actions failed /u01/app/grid/11.2.0/perl/bin/perl -I/u01/app/grid/11.2.0/perl/lib -I/u01/app/grid/11.2.0/crs/install /u01/app/grid/11.2.0/crs/install/rootcrs.pl execution failed USM drivers […]
Oracle Clusterware root.sh fails: Can’t install ohasd service: Inappropriate ioctl for device crsconfig_lib.pm line 5427
Setting up Oracle Clusterware 11.2.0.4 on SuSE Linux Enterprise Server (SLES) SP2 should work flawlessly, but sometimes it does not. 🙂 It turned out that this would become a pair of blog entries. Second one is about “USM driver install actions failed (oracleoks.ko)“. But step by step. On Saturday morning, root.sh failed with the following […]
Oracle on AIX: How to find out the process memory usage
Calculating memory on Unix is tricky business. Especially when a complex software like Oracle Database has shared memory segments like SGA and Code Area. One might be convinced to use the following construction to calculate the overall memory footprint of Oracle processes running on this machine: ps -elf |egrep ” oracle* | ora_.*_* ” | […]
Speaking at COLLABORATE 14: “YOUR machine and MY database – a performing relationship!?”
I’m excited to announce that IOUG accepted my talk “YOUR machine and MY database – a performing relationship!?” for COLLABORATE 14 in Las Vegas. I’d love to see you there – for tech talk, gossip and meeting old and new friends! Abstract: Databases affect machines, machines affect databases. Optimizing one is pointless without knowing the […]
Martin Klier now on twitter
After ignoring the little bird telling things for quite a while, I decided to join the tweeters. Twitter might bring more color into my daily reading. 🙂 If you feel like, just follow me – @MartinKlierDBA […]
Oracle: RHEL6 and Oracle Enterprise Linux 6 certified for Database 11.2.0.3
Hi Linux-DBAs, Red Hat Enterprise Linux 6 and Oracle Enterprise Linux 6 are now certified for Oracle Database 11.2.0.3. Please see this link: https://support.oracle.com/CSP/main/article?cmd=show&id=1441282.1&type=NOT Best regards Martin […]
DOAG Conference 2011 – Impressions and Look-at’s
Once again this year, the German Oracle Users Group has its annual conference and exhibition in Nuremberg. (DOAG Konferenz und Ausstellung 2011, Nürnberg). Being there is nearly a must for Oracle guys in German speaking countries. As usual, here comes my unordered, incomplete and ad-hoc list of things I wrote down to have a closer […]
Oracle Clusterware 11.2: ASM crashes at startup
These days, a customer’s Oracle Clusterware (2 nodes) crashed one ASM instance at every startup. More Facts: It was not possible to start it manually, too. The CSSD was running. For obvious reasons, CRSD did not start. The other ASM instance in the cluster recognized CLUSTER RECONFIGURATION for a short period of time. The ASM […]
Linux Network bonding – setup guide
After looking up Linux bonding stuff for the thrid time, I planned to write an article aubout it. But there are lots of good blog posts on this, so just click here at unixfoo: Linux Network bonding – setup guide (strange link, I know, but it works) Hope it helps for you next high avaliability […]
Native ZFS for Linux
After long-aking FUSE implemented ZFS on Linux, Lawrence Livermore Labs have released a reimplemented ZFS for native use with a Linux Kernel. See details here: http://github.com/behlendorf/zfs Still have to test it, but I’d daresay, it was time. Good pooling Martin […]
AIX: Avoiding “ORA-27126: unable to lock shared memory segment in core”
Did you ever change lock_sga = true for an Oracle Instance on AIX 5.3, and did see ORA-27126: unable to lock shared memory segment in core IBM AIX RISC System/6000 Error: 1: Not owner in Return? Do the following: # vmo -o v_pinshm v_pinshm = 0 # vmo -o v_pinshm=1 Setting v_pinshm to 1 # […]
Oracle 11gR2 ASM / ACFS: A first benchmark (poorly)
Hi folks, since Oracle 11g Release 2 is out now, I had to test one of the most-missed ASM features: the ASM cluster file system ACFS. My Setup: Two VMware nodes with 2 CPUs and 1,5GB of RAM each Oracle Enterprise Linux 5.3 x86_64 Four virtual cluster disks from the ESX server, 10GB in size […]
Oracle 11g JDBC driver hangs blocked by /dev/random – entropy pool empty
On a headless (=without console) network server, the 11g JDBC driver used for (java) application connect may cause trouble. In my case, it refused to connect to the DB without any error, trace or log entry. It simply hung. After several hours, it connected one time, and freezed again. Remote debugging done by the development […]
Setting ulimit -m in AIX
AIX has its own rules, as I have to discover these days. Coming across ulimit, I found out that smitty configures value A here and value B completely elsewhere. Hardest one so far has been “ulimit -m” (“Specifies the size of physical memory, in number of K bytes.” a user can assign), since I could […]
Single Sign On for Apache 2.2 and Active Directory 2003 R2 with SuSE 10.2, mod_auth_kerb and MIT Kerberos
Hi, this is a small howto out of my needs, suggestions are always welcome! Assumptions for this paper You know and basically follow http://www.grolmsnet.de/kerbtut, but there are some facts missing/wrong. 2003R2 KDC’s are 10.0.0.1 and 10.0.0.2 (DNS: dc1.example.com and dc2.example.com) Kerberos Realm for ADS is ADS.EXAMPLE.COM (upper case required!) Web server (hostname.domain) is webhostname.server.example.com DNS […]
Switch workspace on command line
Sometimes, it’s nice to change the current windowmanager workspace on command line, for example if you desire to start a application exactly HERE or THERE. For KDE you may want to do it with “kstart”. But a tool like kstart might not be available for your windowmanager, so have a look at “wmctrl” as well: […]
Oracle 10g Data warehouse ORION benchmark, size 20TB, 1200MB per second
During the last days, I have had the opportunity to test and benchmark a data warehousing hardware, that’s really fast for its money. It’s not suitable for real/available production, since it depends on disk striping over a bunch of components, but I considered it as a good way to push the limits a bit. Result: […]
memlock config for Debian Lenny
Hi, today I tried to start Oracle XE with parameters “pre_paged_sga=true” and “lock_sga=true” on my Debian Lenny toybox. But Lenny has had a rather strict and really sticky value for the user’s maximum amount of pinned memory (ulimit -l) value: 32 (kb). First attempt, change /etc/security/limits.conf: oracle – memlock 1073741824 Result: Nothing, “ulimit -l” as […]
“16 penguins in a row” and a Linux kernel compilation contest (2min 33sec)
A nice view: What’s the story behind? […]
Blocking network loopback slows down firefox extremely
My newly installed Firefox web browser (versions 2 and 3, does not matter) was deadly slow. I don’t mean the display of web sites, no, I am talking about pulldown-menus or opening tabs. (For example, bookmarks folder opens within 6 long seconds.) Several hours I was not able to tell why it acts that way. […]
Talk “Hope is not a strategy” at Vocational School Wiesau
Hi, there will be a talk about IT High Availability for rising IT professionals at Vocational IT School Wiesau on Monday, 10th of March 2008. The topic: “Hope is not a startegy” – IT high availability in theory and practical experience See paper and slides here. Regards Martin EDIT: There has been a nice press […]
New homepage for our Linux User Group Mitterteich
Hi friends, the Linux User Group Mitterteich has a new webpage and a new URI (http://www.linux-mitterteich.de). The old URI (http://www.lug-mitterteich.de.vu) will be redirected from today on. Well, the page isn’t perfect at the moment – but finally we started working on it: The free template (made by Ramin Hossaini) used at the moment will be […]
My first steps with Gentoo – Part I
Hi, saw some friends of mine using Gentoo for useful purposes (only had experience with Gentoo users asking useless questions and/or causing deeply clueless arguments about the use of a portage based OS so far), I needed to check it myself. First thing, loaded a minimalistic Gentoo 2007.0 .iso file onto my VMware server, and […]
Picture alignment trouble for 1680×1050 resolution (WXGA)? Use xvidtune!
Hi, just got a brand-new LG L226 WTQ and it refused to align the picture properly, the auto set feature left a full of 15cm on the left unused and black, and same 15cm on the right hidden. Changing position of the picture manually (by drive down the “HORIZONTAL” value to zero) reduced the black/hidden […]
Kerberos auth with Apache 2.2 and Microsoft Active Directory
Hi, just a note: Have a look at http://www.grolmsnet.de/kerbtut/ It’s not perfect, but my additions will follow as soon as my prototype here is running well. At the moment it does, but I do not fully understand why 🙂 Regards Usn […]
run Cisco VPN client as non-root-user
Hello, if you want to run the vpnclient as non-root-user (very desirable), you probably will get privsep: unable to drop privileges: group set failed. since the cvpnd needs to be run with root privileges. Just give it the setuid root-Flag: chmod 4111 /opt/cisco-vpnclient/bin/cvpnd and have fun with yout user-built VPN tunnel. Regards, Usn […]
new GNU bash forum rising
Hi, TheBonsai started a brand-new bash forum at http://forum.bash-hackers.org. Since I know him as a real skilled bash poweruser it should be fun to learn from the site. Just have a look. Yours, Usn […]
Apache 2.2 – “unable to include potential exec”
Hi, recently I’ve seen ugly error pages (e.g.for 404 or 403) on my Apache 2.2 server: The supplemental text blocks have been there, but instead of header, footer and spaces “[an error occured while processing this directive]” was shown. For these accesses, the Apache error.log showed “unable to include potential exec ‘include/top.html’ in parsed file […]
Prepare IPtables for the Cisco VPN Client
Hi out there, installing the Cisco VPN Client 4.8.00 should be no problem (just run “vpninstall” with kernel headers installed). But running it from the notebook in an insecure environment needs a host firewall on the mobile device. I love setting the default policies of a chain to “DROP”! But the VPN Client communicates via […]
How to create a self-signed OpenSSL certificate
Hi folx, if you want to create a self-signed certificate with OpenSSL (useful for encryption-only purposes, e.g. your own mailserver) just do the following: openssl req -x509 -nodes -days 365 -subj ‘/C=DE/ST=Bayern/L=Munich/CN=www.example.com’ -newkey rsa:2048 -keyout key4cert.pem -out cert.pem It means: “-nodes” makes the key unencrypted “-days” makes it valid for n days “-subj” provides your […]