Standby monitor

select * from V$ARCHIVE_GAP

Standby log errors

Error

FAL[client]: Failed to request gap sequence 
 GAP - thread 1 sequence 2-101
 DBID 2236488982 branch 665833900
FAL[client]: All defined FAL servers have been attempted.

Solution
crosscheck archivelog all;

SGA exceeds 2GB on Linux 32bit

1. edit init.ora

use_indirect_data_buffers=true 
db_block_size=8192 
db_block_buffers=1048576 # 8Gb
shared_pool_size=1415577600 #2831155200 - 2G

Grant/Revoke object privileges

begin
  for cur in (select do.owner || '.' || do.object_name obj
                from dba_objects do
               where do.owner = 'user1'
                 and do.object_type = 'TABLE') loop
    execute immediate 'grant select on ' || cur.obj || ' to user2';
    --execute immediate 'revoke select on '||cur.obj ||' from user2';
    dbms_output.put_line(cur.obj);
  end loop;
end;

OEL Installation options

Packages selection
Applications
- Grafical Internet
Development Tools
- Development Libraries
- Development Tools
- GNOME Software Development
- Java Development
- Legacy Software Development
- X Software Development
   Optional Packages
   - libXP-devel
   - openmotif-devel
Base System
- Legacy Software Support
   Optional packages
   - compat-db
- System Tools
   Optional packages
   - sysstat

Linux kernel parameters for Oracle installation

1) Edit file /etc/sysctl.config
example RAM8Gb
kernel.shmmax = 2147483648 #max RAM
kernel.shmall = 2097152
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default=1048576
net.core.rmem_max=1048576
net.core.wmem_default=262144
net.core.wmem_max=262144