OTNYathra2017 @Mumbai

 

I have provided enough information about the OTN Yathra, In my previous artical “about-otnyatha”

In this artical I have decided to sharing my experiences about the sessions which i have been attended.

I have choose the Mumbai location because it is near to Ahmedabad.

I had attended below sessions at OTN Yathra 2017 @Mumbai organized by AIOUG / OUAG

1.)  “High Performance Database in Oracle Bare Metal Cloud Services” by Vivek Sharma

This session was mainly focus on Oracle Bare Metal Cloud Services offering and options by Oracle.

2.)   “Oracle and Docker – Everything you want to know to run your workload in docker container” by Umesh Tanna

I was really impress by Umesh, the way he is explaining the docker and oracle offering was quite good.

3.)  Oracle GoldenGate – IRCTC by Veeratteshwaran

This session has change my perception about the replication technology.

4.)  Building Private Cloud with Open Infrastructure by Nitin Gupta

This is the best session that actually I’m interested to know what is offering and differce option of oracle in Open Infrastructure.

5.)  12 things DBA’s will love about 12.2 by Connor McDonald

I’m feeling lucky that i choose this session because Connor is great presentation skills and sharing his experience with different examples

These all sessions were really helpful and it’s help me lots to to fill with new angle of thinking amount the upcoming technologies

I’m really greatfull to all the volunteers of AIOUG and specific to Mumbai Local Chepter volunteers who had nicely organized this event.

I’m also thankful to all the sponsors.

If you have any quesions or queries please comment here, I’m happy to share my own views and experiences about these new technologies.

Happy Learning …

About OTNYathra

OTNYathra is one day event which is organized by AIOUG / Oracle Community ACE / ACE Directors / OUG Evangelists on every year.

This is series of six conferences across six major cities (Chennai,Bangalore,Hyderabad,Pune,Mumbai,Gurgaon)

Mostly there are three parallel classroom sessions are going on so you can decide and seat in your interested session.

This is not a commercial event, They are collecting Rs. 500 as registration fee to cover the Lunch/Tee/Coffee/Snacks and other logistics to host the event.

I’m regularly attend this event since 2014.

As per my opinion this is the best technical one day event that i recommended to attend to all the DBA and Developers.

AIOUG also started local chapter in all above region.

I hope that AIOUG Gujarat Chapter will start officially very soon.

You can check latest information on my OTN Blog
https://community.oracle.com/blogs/hiteshgondalia/2017/05/16/aioug-gujarat-chapter

Website: http://otnyathra.in

You can check session information using this link(http://otnyathra.in/{name of city}/)
http://otnyathra.in/mumbai

Link to register in event
http://otnyathra.in/register

Disabling Transparent HugePages in RHEL7.x

Environment
[root@lab-12cr2 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.0 (Maipo)

Runtime Disable THP
Append below lines in /etc/rc.local
if test -f /sys/kernel/mm/transparent_hugepage/enabled; then
echo never > /sys/kernel/mm/transparent_hugepage/enabled
fi
if test -f /sys/kernel/mm/transparent_hugepage/defrag; then
echo never > /sys/kernel/mm/transparent_hugepage/defrag
fi
Make sure that rc.local is running on reboot
chmod +x /etc/rc.d/rc.local
systemctl enable rc-local
systemctl status rc-local

Check the behavior on post reboot the operating system

[root@lab-12cr2 ~]# cat /sys/kernel/mm/transparent_hugepage/enabled
always madvise [never]
[root@lab-12cr2 ~]#
[root@lab-12cr2 ~]# cat /sys/kernel/mm/transparent_hugepage/defrag
always madvise [never]
[root@lab-12cr2 ~]#
[root@lab-12cr2 ~]# grep -i HugePages_Total /proc/meminfo
HugePages_Total: 0
[root@lab-12cr2 ~]# cat /proc/sys/vm/nr_hugepages
0
[root@lab-12cr2 ~]# grep -i AnonHugePages /proc/meminfo
AnonHugePages: 2048 kB

Permanent Disable THP
Oracle Linux 7 is similar, but uses GRUB2 so you need to edit the “/boot/grub2/grub.cfg” file using the grubby command.
[root@lab-12cr2 ~]# grubby –default-kernel
/boot/vmlinuz-3.10.0-123.el7.x86_64
[root@lab-12cr2 ~]# grubby –args=”transparent_hugepage=never” –update-kernel /boot/vmlinuz-3.10.0-123.el7.x86_64
[root@lab-12cr2 ~]# grubby –info /boot/vmlinuz-3.10.0-123.el7.x86_64
index=0
kernel=/boot/vmlinuz-3.10.0-123.el7.x86_64
args=”ro rd.lvm.lv=rhel/root crashkernel=auto rd.lvm.lv=rhel/swap vconsole.font=latarcyrheb-sun16 vconsole.keymap=us rhgb quiet LANG=en_US.UTF-8 transparent_hugepage=never”
root=UUID=8190d97a-a2e9-44cd-9810-804def1d6f89
initrd=/boot/initramfs-3.10.0-123.el7.x86_64.img
title=Red Hat Enterprise Linux Server, with Linux 3.10.0-123.el7.x86_64
[root@lab-12cr2 ~]#

[root@lab-12cr2 ~]# grep -i “transparent_hugepage=never” /boot/grub2/grub.cfg
linux16 /vmlinuz-3.10.0-123.el7.x86_64 root=UUID=8190d97a-a2e9-44cd-9810-804def1d6f89 ro rd.lvm.lv=rhel/root crashkernel=auto rd.lvm.lv=rhel/swap vconsole.font=latarcyrheb-sun16 vconsole.keymap=us rhgb quiet LANG=en_US.UTF-8 transparent_hugepage=never
[root@lab-12cr2 ~]# grep -i AnonHugePages /proc/meminfo
AnonHugePages: 0 kB
[root@lab-12cr2 ~]#
[root@lab-12cr2 ~]# grep -i HugePages_Total /proc/meminfo
HugePages_Total: 0
[root@lab-12cr2 ~]# cat /proc/sys/vm/nr_hugepages
0

Reference
Oracle MetaLink ALERT: Disable Transparent HugePages on SLES11, RHEL6, RHEL7, OL6, OL7 and UEK2 Kernels (Doc ID 1557478.1)

https://oracle-base.com/articles/linux/configuring-huge-pages-for-oracle-on-linux-64#disabling-transparent-hugepages

http://docs.oracle.com/database/122/LADBI/disabling-transparent-hugepages.htm#LADBI-GUID-02E9147D-D565-4AF8-B12A-8E6E9F74BEEA

Behavior Changes of RHEL 7.x Operating System

RHEL 7.x had taken lots of changes by default …

1.) Default file system changes: XFS
In RHEL7 /CentOS 7 and Oracle Linux have adopted XFS as their default file system.
Apart of these there are other numerous changes that you could find from faq forum like http://simplylinuxfaq.blogspot.in/p/major-difference-between-rhel-7-and-6.html

Some of them i found to be mandatory change before use it for Database Server in Production.
2.) Default HugePages is On On
Oracle recommends that you disable Transparent HugePages before you start installation.

3.) Default Setting RemoveIPC=yes
Setting RemoveIPC=yes on Redhat 7.2 Crashes ASM and Database Instances as Well as Any Application That Uses a Shared Memory Segment (SHM) or Semaphores (SEM)

Recommended to follow below steps
1. Set RemoveIPC=no in /etc/systemd/logind.conf
2. Reboot the server or restart systemd-logind as follows:
# systemctl daemon-reload
# systemctl restart systemd-logind

RHEL7: rc.local service not starting

Found this on some Red Hat blog:

“Systemd is a system and service manager for Linux operating systems. It is designed to be backwards compatible with SysV init scripts, and provides a number of features such as parallel startup of system services at boot time, on-demand activation of daemons, support for system state snapshots, or dependency-based service control logic. In Red Hat Enterprise Linux 7, systemd replaces Upstart as the default init system.”

chmod +x /etc/rc.d/rc.local
systemctl enable rc-local
systemctl status rc-local

https://grepora.com/2016/07/15/rhel7-rc-local-service-not-starting/

Remove Extra member from standby redo group

Tips , Reset below parameters before create standby redo group
db_create_online_log_dest_1=+DATA1 and db_create_online_log_dest_2=+DATA2

If you have set these parameters and you create standby redo log then it will be multiplexed in +DATA1 and +DATA2, Not recommended in Prod:)

@Primary
SQL> show parameter standby_file_management=MANUAL;
SQL> alter system set standby_file_management=MANUAL;

System altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_5.319.922465363’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_6.310.922465367’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_7.311.922465371’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_8.299.922465375’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_9.872.922465379’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_10.874.922465383’;

Database altered.

SQL> select member from v$logfile;

MEMBER
——————————————————————————–
+ORADATA/BLRDB/ONLINELOG/group_2.305.922465353
+ORADATA/BLRDB/ONLINELOG/group_2.622.922465353
+ORADATA/BLRDB/ONLINELOG/group_1.307.922465349
+ORADATA/BLRDB/ONLINELOG/group_1.306.922465351
+ORADATA/BLRDB/ONLINELOG/group_3.620.922465355
+ORADATA/BLRDB/ONLINELOG/group_3.323.922465357
+ORADATA/BLRDB/ONLINELOG/group_4.322.922465359
+ORADATA/BLRDB/ONLINELOG/group_4.320.922465361
+ORADATA/BLRDB/ONLINELOG/group_5.313.922465365
+ORADATA/BLRDB/ONLINELOG/group_6.301.922465369
+ORADATA/BLRDB/ONLINELOG/group_7.302.922465373

MEMBER
——————————————————————————–
+ORADATA/BLRDB/ONLINELOG/group_8.300.922465377
+ORADATA/BLRDB/ONLINELOG/group_9.873.922465381
+ORADATA/BLRDB/ONLINELOG/group_10.875.922465385
+ORADATA/BLRDB/ONLINELOG/group_11.1351.927649007

15 rows selected.

SQL> show parameter standby_file_management=AUTO scope=both;
SQL> ALTER SYSTEM SET standby_file_management=AUTO scope=both;

System altered.

SQL> select member from v$logfile;

MEMBER
——————————————————————————–
+ORADATA/BLRDB/ONLINELOG/group_2.305.922465353
+ORADATA/BLRDB/ONLINELOG/group_2.622.922465353
+ORADATA/BLRDB/ONLINELOG/group_1.307.922465349
+ORADATA/BLRDB/ONLINELOG/group_1.306.922465351
+ORADATA/BLRDB/ONLINELOG/group_3.620.922465355
+ORADATA/BLRDB/ONLINELOG/group_3.323.922465357
+ORADATA/BLRDB/ONLINELOG/group_4.322.922465359
+ORADATA/BLRDB/ONLINELOG/group_4.320.922465361
+ORADATA/BLRDB/ONLINELOG/group_5.313.922465365
+ORADATA/BLRDB/ONLINELOG/group_6.301.922465369
+ORADATA/BLRDB/ONLINELOG/group_7.302.922465373

MEMBER
——————————————————————————–
+ORADATA/BLRDB/ONLINELOG/group_8.300.922465377
+ORADATA/BLRDB/ONLINELOG/group_9.873.922465381
+ORADATA/BLRDB/ONLINELOG/group_10.875.922465385
+ORADATA/BLRDB/ONLINELOG/group_11.1351.927649007

15 rows selected.

SQL>
SQL> alter system switch logfile;

System altered.

SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.1

@DR

alter system set standby_file_management=MANUAL;
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_5.319.922465363’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_6.310.922465367’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_7.311.922465371’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_8.299.922465375’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_9.872.922465379’;

Database altered.

SQL> ALTER DATABASE DROP STANDBY LOGFILE MEMBER ‘+ORADATA/BLRDB/ONLINELOG/group_10.874.922465383′;

Database altered.

Standby redo logs without multiplexting:-

SQL> SELECT MEMBER FROM V$LOGFILE WHERE TYPE=’STANDBY’;

MEMBER
——————————————————————————–
+ORADATA/BLRDB/ONLINELOG/group_5.313.922465365
+ORADATA/BLRDB/ONLINELOG/group_6.301.922465369
+ORADATA/BLRDB/ONLINELOG/group_7.302.922465373
+ORADATA/BLRDB/ONLINELOG/group_8.300.922465377
+ORADATA/BLRDB/ONLINELOG/group_9.873.922465381
+ORADATA/BLRDB/ONLINELOG/group_10.875.922465385

SQL> SELECT GROUP#,THREAD#,STATUS FROM V$STANDBY_LOG;

GROUP# THREAD# STATUS
———- ———- ———-
5 1 UNASSIGNED
6 1 UNASSIGNED
7 1 UNASSIGNED
8 2 UNASSIGNED
9 2 UNASSIGNED
10 2 UNASSIGNED