Durham Oracle

Oracle New Features

This is an excellent video on probably the two big features going forward with Oracle 19.

Planning to run some Oracle 19 installations and patch at the same time and use the read only feature of the Oracle Home. Will post updates and let you know how I get on but in the meantime suggest you watch this video.

Oracle Cloud new instance

I wanted a new test environment so re-created two instances on the always free option for the Oracle Cloud Infrastructure.

Two things which I could not remember from the last time I did this was that the private key that you download when creating the instance, when you use login vi putty you hit an error.

Basically the private key from OCI, the putty application does not like it, so you have to import and change it to a version that it does. Just need puttygen.

https://www.puttygen.com/convert-pem-to-ppk

Or from the command line -

$ puttygen ssh-key-test.key -o private -o ssh-key-test.ppk

just use the OCI generated key and change it to .ppk as above.

I tend to follow the notes from the excellent Oracle Base website to install Oracle but when using MobaXterm to run say the graphical Oracle Installer, after a fresh build on Oracle OCI instance you need to change the X11UseLocalhost parameter. Worth changing this to use password authentication at the same time so not dependent on using private keys (this is a test box for me so happy with just a password).

https://docs.oracle.com/en-us/iaas/Content/Resources/Assets/whitepapers/run-graphical-apps-securely-on-oci.pdf

If you want to install "figlet" which I use quite a lot you need to add this :

sudo rpm -ivh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

https://snapcraft.io/install/figlet/rhel

After succesfully installing oracle 19c (follow the notes from Oracle Base) and fighting 19c with 1gig of memory when trying to connect the two servers needed to add port 1521 -

[root@durdb01 etc]# firewall-cmd --permanent --add-port=1521/tcp

success

[root@durdb01 etc]# firewall-cmd --reload

success

[root@durdb01 ~]# firewall-cmd --list-all
public (active)
target: default
icmp-block-inversion: no
interfaces: ens3
sources:
services: dhcpv6-client ssh
ports: tcp/1521 5556/tcp 9001/tcp 7777/tcp 14021/tcp 5557/tcp
protocols:
masquerade: no
forward-ports:
source-ports:
icmp-blocks:
rich rules:

As OCI always free is limited to 1gig had to set the oracle memory parameters as :

memory_max_target big integer 772M
memory_target big integer 0

Added 8gig of swap - not a lot of memory to play with but then it is free.

Useful link - DataGuard using OCI:

https://docs.oracle.com/en-us/iaas/Content/Database/Tasks/usingdataguard.htm

Relinking Oracle Grid Home on RAC

Couple of notes from Oracle Metalink when relinking Oracle and Grid Home.

How To Relink The Oracle Grid Infrastructure Standalone (Restart) Installation Or Oracle Grid Infrastructure RAC/Cluster Installation (11.2 to 18.c). (Doc ID 1536057.1)

Please note when relinking the grid home the /u01/app/oraInventory/locks directory had to have the permissions changed when the grid relink ran otherwise the relink did not work.

Also, after bringing back some of our boxes and running "crsctl start crs" the cluster was not starting on that node.

After running "oracleasm listdisks" - it turned out some of the diskgroups were missing.

Under investigation.

We ran "oracleasm scandisks" which discovered the disks but still no success with "crsctl stat res -t"

The only option was to run "crstcl stop crs -f" and force it down.

Once restarted the server was ok.

Please check that oracleasm scandisks returns the expected values prior to running crsctl start crs.

The text in red are the commands to run once you have stopped all the services on the node you are about to relink.

https://www.durham.computer/2020/04/stopping-node-in-oracle-rac-12c.html

If you need to "bounce" the server say for a kernel update please run "crsctl disable crs" or the clustering will start once the server restarts and you will have to stop everything again. Please remember to "crsctl enable crs" when you are happy.

Abridged notes from the Metalink Note 1536057.1) :

How To Relink The Oracle Grid Infrastructure RAC/Cluster Installation - v12.2

In order to relink the Oracle Grid Infrastructure RAC/Cluster Installation, please follow the next steps after stopping all the services running:

1) As root OS user, please unlock the Grid Infrastructure Oracle Home (on every node) as follows (set the correct grid home env first) :

# cd < Grid Infrastructure Oracle Home >/crs/install
# rootcrs.sh -unlock

2) As the Oracle Grid Infrastructure owner (on every node) relink the Grid Infrastructure Oracle Home as follows:

$ export ORACLE_HOME=< Grid Infrastructure Oracle Home >
$ < Grid Infrastructure Oracle Home>/bin/relink all

3) As root OS user again, please execute the next commands (on every node):

# cd < Grid Infrastructure Oracle Home >/rdbms/install/
# ./rootadd_rdbms.sh
# cd < Grid Infrastructure Oracle Home >/crs/install
# rootcrs.sh -lock

Then "crsctl start crs" - please see note above re oracleasm listdisks

Note: CRS services (CRS, CSS ASM instances, diskgroups, listeners, DB instances, etc.) will automatically start.

4) Please review the relink.log file located at the following directory (to confirm or discard any error):

$ < Grid Infrastructure Oracle Home>/install/relink.log