Fast Free Public DNS Servers List

As you might already know that DNS is to translate hostnames into IP addresses. For example, google.com into 209.85.175.105. You can simply compare it to your mobile phone book. Just you type person's name and then it is converted to his phone number while dialing.

I was using my own ISP server DNS addresses(specifically Banglalion Wimax in Bangladesh) and then I saw its DNS can't resolve many IP addresses like blogspot.com and several others. Even it can't download any attachment from gmail due to DNS problem. I ringed their support but they could not resolve the problem. So, I wanted to mention here some fast free public DNS servers list so that you can use them in your network configuration.

Here goes some list of better, fast public dns servers and of course free dns server (you can use it compared to your ISP / DSL / ADSL / cable DNS service providers dns servers). Even with these DNS servers you can expect faster browser speed. And most of them almost resolve all hostnames.

A)Service provider: Google
Google public dns server list:

8.8.8.8
8.8.4.4
B)Service provider: Dnsadvantage
Dnsadvantage free dns server list:

156.154.70.1
156.154.71.1

C)Service provider: OpenDNS
OpenDNS free dns server list:

208.67.222.222
208.67.220.220

D)Service provider: Norton
Norton free dns server list:

198.153.192.1
198.153.194.1

E)Service provider: Verizon
Public dns server list:

4.2.2.1
4.2.2.2
4.2.2.3
4.2.2.4
4.2.2.5
4.2.2.6

F)Service provider: ScrubIt
Public dns server list:

67.138.54.100
207.225.209.66

Check whether required packages are installed on Red Hat Linux to install Oracle 11gR2

1)Asianux 3, Oracle Enterprise Linux 5, and Red Hat Enterprise Linux 5
[root@OBL-INTDB ~]# rpm -q binutils-2.17.50.0.6 compat-libstdc++-33-3.2.3 compat-libstdc++-33-3.2.3 elfutils-libelf-0.125 elfutils-libelf-devel-0.125 gcc-4.1.2 gcc-c++-4.1.2 glibc-2.5-24 glibc-2.5-24 glibc-common-2.5 glibc-devel-2.5 glibc-devel-2.5 glibc-headers-2.5 ksh-20060214 libaio-0.3.106 libaio-0.3.106 libaio-devel-0.3.106 libaio-devel-0.3.106 libgcc-4.1.2 libgcc-4.1.2 libstdc++-4.1.2 libstdc++-4.1.2 libstdc++-devel 4.1.2 make-3.81 numactl-devel-0.9.8.x86_64 sysstat-7.0.2 unixODBC-2.2.11 unixODBC-2.2.11 unixODBC-devel-2.2.11 unixODBC-devel-2.2.11

package bcompat-libstdc++-33-3.2.3 is not installed
package bcompat-libstdc++-33-3.2.3 is not installed
package elfutils-libelf-0.125 is not installed
package elfutils-libelf-devel-0.125 is not installed
gcc-4.1.2-48.el5
gcc-c++-4.1.2-48.el5
package glibc-2.5-24 is not installed
package glibc-2.5-24 is not installed
glibc-common-2.5-49.el5_5.7
glibc-devel-2.5-49.el5_5.7
glibc-devel-2.5-49.el5_5.7
glibc-devel-2.5-49.el5_5.7
glibc-devel-2.5-49.el5_5.7
glibc-headers-2.5-49.el5_5.7
package ksh-20060214 is not installed
libaio-0.3.106-5
libaio-0.3.106-5
libaio-0.3.106-5
libaio-0.3.106-5
package libaio-devel-0.3.106 is not installed
package libaio-devel-0.3.106 is not installed
libgcc-4.1.2-48.el5
libgcc-4.1.2-48.el5
libgcc-4.1.2-48.el5
libgcc-4.1.2-48.el5
libstdc++-4.1.2-48.el5
libstdc++-4.1.2-48.el5
libstdc++-4.1.2-48.el5
libstdc++-4.1.2-48.el5
libstdc++-devel-4.1.2-48.el5
package 4.1.2 is not installed
make-3.81-3.el5
package numactl-devel-0.9.8.x86_64 is not installed
package sysstat-7.0.2 is not installed
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
package unixODBC-devel-2.2.11 is not installed
package unixODBC-devel-2.2.11 is not installed

Asianux 2, Oracle Enterprise Linux 4, and Red Hat Enterprise Linux 4
[root@OBL-INTDB ~]# rpm -q binutils-2.15.92.0.2 compat-libstdc++-33-3.2.3 compat-libstdc++-33-3.2.3 elfutils-libelf-0.97 elfutils-libelf-devel-0.97 expat-1.95.7 gcc-3.4.6 gcc-c++-3.4.6 glibc-2.3.4-2.41 glibc-2.3.4-2.41 glibc-common-2.3.4 glibc-devel-2.3.4 glibc-headers-2.3.4 libaio-0.3.105 libaio-0.3.105 libaio-devel-0.3.105 libaio-devel-0.3.105 libgcc-3.4.6 libgcc-3.4.6 libstdc++-3.4.6 libstdc++-3.4.6 libstdc++-devel 3.4.6 make-3.80 numactl-0.6.4.x86_64 pdksh-5.2.14 sysstat-5.0.5 unixODBC-2.2.11 unixODBC-2.2.11 unixODBC-devel-2.2.11 unixODBC-devel-2.2.11

package binutils-2.15.92.0.2 is not installed
compat-libstdc++-33-3.2.3-61
compat-libstdc++-33-3.2.3-61
compat-libstdc++-33-3.2.3-61
compat-libstdc++-33-3.2.3-61
package elfutils-libelf-0.97 is not installed
package elfutils-libelf-devel-0.97 is not installed
package expat-1.95.7 is not installed
package gcc-3.4.6 is not installed
package gcc-c++-3.4.6 is not installed
package glibc-2.3.4-2.41 is not installed
package glibc-2.3.4-2.41 is not installed
package glibc-common-2.3.4 is not installed
package glibc-devel-2.3.4 is not installed
package glibc-headers-2.3.4 is not installed
package libaio-0.3.105 is not installed
package libaio-0.3.105 is not installed
package libaio-devel-0.3.105 is not installed
package libaio-devel-0.3.105 is not installed
package libgcc-3.4.6 is not installed
package libgcc-3.4.6 is not installed
package libstdc++-3.4.6 is not installed
package libstdc++-3.4.6 is not installed
libstdc++-devel-4.1.2-48.el5
package 3.4.6 is not installed
package make-3.80 is not installed
package numactl-0.6.4.x86_64 is not installed
package pdksh-5.2.14 is not installed
package sysstat-5.0.5 is not installed
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
unixODBC-2.2.11-7.1
package unixODBC-devel-2.2.11 is not installed
package unixODBC-devel-2.2.11 is not installed

3) SUSE Linux Enterprise Server 10

rpm -q binutils-2.16.91.0.5  compat-libstdc++-5.0.7  gcc-4.1.0  gcc-c++-4.1.2  glibc-2.4-31.63  glibc-devel-2.4-31.63  glibc-devel-32bit-2.4-31.63  ksh-93r-12.9  libaio-0.3.104  libaio-32bit-0.3.104  libaio-devel-0.3.104  libaio-devel-32bit-0.3.104  libelf-0.8.5  libgcc-4.1.2  libstdc++-4.1.2  libstdc++-devel-4.1.2  make-3.80  numactl-0.9.6.x86_64  sysstat-8.0.4

4) SUSE Linux Enterprise Server 11

rpm -q binutils-2.19  gcc-4.3  gcc-32bit-4.3  gcc-c++-4.3  glibc-2.9  glibc-32bit-2.9  glibc-devel-2.9  glibc-devel-32bit-2.9  ksh-93t  libaio-0.3.104  libaio-32bit-0.3.104  libaio-devel-0.3.104  libaio-devel-32bit-0.3.104  libstdc++33-3.3.3  libstdc++33-32bit-3.3.3  libstdc++43-4.3.3_20081022  libstdc++43-32bit-4.3.3_20081022  libstdc++43-devel-4.3.3_20081022  libstdc++43-devel-32bit-4.3.3_20081022  libgcc43-4.3.3_20081022  libstdc++-devel-4.3  make-3.81  sysstat-8.1.5

Security - Users, Privileges, Roles, And Synonyms - Quiz

1. (TCO A) Evaluate this SQL script:

CREATE USER hr IDENTIFIED BY hr01;
CREATE ROLE hr_manager;
CREATE ROLE hr_clerk;
GRANT hr_clerk TO hr_manager;
CREATE ROLE hr_director;
GRANT hr_manager TO hr_director;
GRANT hr_director TO hr
/

How many roles will the HR user have access to? (Points: 3)
 0 
 1 
 2 
 3 


2. (TCO A) Evaluate the SQL Script:

Create role payroll;
create role sales_dept;
create role inventory
create user scott identified by tiger;
grant select on employee to payroll;
grant select on sale to sales_dept;
grant payroll to sales_dept;
grant sales_dept to inventory;
grant inventory to scott;

What tables can SCOTT query? (Points: 3)
 Only sale 
 Only employee 
 Both sale and employee 
 Neither sale nor employee 


3. (TCO A) You issue this command:

Grant update on employee to Sally with grant option;

Which task could Sally perform on the employee table? (Points: 3)
 View data 
 Delete data 
 Modify constraints 
 Give update access to other users 


4. (TCO A) Your manager wants to conduct an audit of all privileges that each user in the database has. You know there are over 500 users. State why this is not a trivial request given the number of ways a user can grant or receive privileges. (Points: 10)
 
 

Password Policy Management in Oracle 10g and 11g

1. TCO G - Locking a user with the ____ clause (of the CREATE USER or ALTER USER commands) completely locks this user out of the database.(Points: 2)
 LOCK 
 ACCOUNT LOCK 
 BLOCK 
 ACCOUNT BLOCK 


2. TCO G - A(n) ____ is a collection of settings that limits the use of system resources and the database. (Points: 2)
 privilege 
 group 
 profile 
 role 


3. TCO G - The default profile, named ____, has no limits on resources or database use. (Points: 2)
 DEFPROF 
 PROFILE 
 USER 
 DEFAULT 


4. TCO G - When you plan to adjust resource limits in any Oracle 10g database, you must first change the initialization parameter named ____. (Points: 2)
 RESOURCE_LIMITS 
 CPU_PER_CALL 
 PROFILE_LIMIT 
 COMPOSITE_LIMIT 


5. TCO G - Resources can be set to zero using the ____ statement. (Points: 2)
 ALTER RESOURCE 
 ALTER RESOURCE VALUE 
 ALTER RESOURCE COST 
 ALTER RESOURCE DEFAULT 


6. TCO G - To view the resource settings for the system, you should type and run this query: ____. (Points: 2)
 SELECT * FROM RESOURCES; 
 SELECT * FROM RESOURCE_SETTING; 
 SELECT * FROM RESOURCE_SETTINGS; 
 SELECT * FROM RESOURCE_COST; 


7. TCO G - You should click on the ____ tab of a user's property sheet (available in the Security Management section of the Enterprise Manager console) to see a list of the quotas for each tablespace. (Points: 2)
 General 
 Role 
 System 
 Quota 


8. TCO G - The ____ object privilege allows you to create FOREIGN KEY constraints that reference the table. (Points: 2)
 REFERENCES 
 FOREIGN KEY 
 CONSTRAINT 
 INDEX 


9. TCO G - The OS_AUTHENT_PREFIX parameter is null. You log on to your computer as JOEBANKS and then issue this command:

sqlplus /

The connect request fails. Which statement is true?

(Points: 2)
 The database prompts you for a password. 
 The database connects you as OPS$JOEBANKS. 
 The database cannot connect you because no prefix is specified. 
 The database connects you as JOEBANKS. 
 None of the above. 


10. TCO G - You are the DBA and you run the following SQL commands:

CREATE USER MYEE IDENTIFIED BY MYEE
DEFAULT TABLESPACE USERS
PROFILE MANAGER_PROFILE
PASSWORD EXPIRE;

GRANT CREATE SESSION TO MYEE;

CONNECT MYEE/MYEE;

What happens next?

(Points: 2)
 You connect as the MYEE user. 
 You are prompted to change the password for MYEE. 
 You cannot log on because the password is expired. 
 You cannot log on because MYEE does not have the RESOURCE role. 

Privilege Related Quiz in Oracle

1. (TCO A) Which condition must be met for a user to give SELECT privileges on the CUSTOMER table to everyone using the PUBLIC keyword? (Points: 3)
        A) Must have SELECT privileges 
        B) Must own the CUSTOMER table 
        C) Must have been granted the PUBLIC privilege 
        D) Must have been granted the SELECT privilege WITH GRANT OPTION 
        Either B or D 


2. (TCO A) What privileges can Jim grant on his tables? (Points: 3)
        Revoke 
        Grant 
        Execute 
        All 


3. (TCO A)  You execute the following query, which returns an error:

Grant Select any table with GRANT OPTION;

What is the most likely cause of the error? (Points: 3)
        You do not have the SELECT ANY TABLE object privilege. 
        The WITH GRANT OPTION is for system privileges. 
        The WITH GRANT OPTION is for object privileges. 
        You do not have the SELECT ANY TABLE system privilege. 


4. (TCO A) You have just been promoted as a database administrator. You have been requested to evaluate some aspects of security. Immediately you learn that all accounts have been granted the RESOURCE role. Most of the users are not allowed to to have the privileges granted by this role.

Briefly state the problems associated with the RESOURCE role and write two statement that

1. removes the role from a user (JDOE) and
2. grants the user the privilege to connect to the database.

(Points: 10)

 

Database Applications and Programming Week 7 Homework and Quiz

1. TCO E: What are the three types of parameters that used in procedural language constructs? Describe the characteristics of each.

2. TCO G: Describe what a stored procedure is. Describe the benefits of using a stored procedure.

3. Analyze the file from Doc Share called utlpwdmg.sql and analyze the code in this file. Write a paragraph that describes what the function performs. What are the inputs parameters, the output parameter and what does the function do?

utlpwdmg.sql contents

Rem
Rem $Header: utlpwdmg.sql 31-aug-2000.11:00:47 nireland Exp $
Rem
Rem utlpwdmg.sql
Rem
Rem  Copyright (c) Oracle Corporation 1996, 2000. All Rights Reserved.
Rem
Rem    NAME
Rem      utlpwdmg.sql - script for Default Password Resource Limits
Rem


CREATE OR REPLACE FUNCTION verify_function
(username varchar2,
  password varchar2,
  old_password varchar2)
  RETURN boolean IS 
   n boolean;
   m integer;
   differ integer;
   isdigit boolean;
   ischar  boolean;
   ispunct boolean;
   digitarray varchar2(20);
   punctarray varchar2(25);
   chararray varchar2(52);

BEGIN 
   digitarray:= '0123456789';
   chararray:= 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
   punctarray:='!"#$%&()``*+,-/:;<=>?_';

   -- Check if the password is same as the username
   IF NLS_LOWER(password) = NLS_LOWER(username) THEN
     raise_application_error(-20001, 'Password same as or similar to user');
   END IF;

   -- Check for the minimum length of the password
   IF length(password) < 4 THEN
      raise_application_error(-20002, 'Password length less than 4');
   END IF;

   -- Check if the password is too simple. A dictionary of words may be
   -- maintained and a check may be made so as not to allow the words
   -- that are too simple for the password.
   IF NLS_LOWER(password) IN ('welcome', 'database', 'account', 'user', 'password', 'oracle', 'computer', 'abcd') THEN
      raise_application_error(-20002, 'Password too simple');
   END IF;

   -- Check if the password contains at least one letter, one digit and one
   -- punctuation mark.
   -- 1. Check for the digit
   isdigit:=FALSE;
   m := length(password);
   FOR i IN 1..10 LOOP 
      FOR j IN 1..m LOOP 
         IF substr(password,j,1) = substr(digitarray,i,1) THEN
            isdigit:=TRUE;
             GOTO findchar;
         END IF;
      END LOOP;
   END LOOP;
   IF isdigit = FALSE THEN
      raise_application_error(-20003, 'Password should contain at least one digit, one character and one punctuation');
   END IF;
   -- 2. Check for the character
   <<findchar>>
   ischar:=FALSE;
   FOR i IN 1..length(chararray) LOOP 
      FOR j IN 1..m LOOP 
         IF substr(password,j,1) = substr(chararray,i,1) THEN
            ischar:=TRUE;
             GOTO findpunct;
         END IF;
      END LOOP;
   END LOOP;
   IF ischar = FALSE THEN
      raise_application_error(-20003, 'Password should contain at least one \
              digit, one character and one punctuation');
   END IF;
   -- 3. Check for the punctuation
   <<findpunct>>
   ispunct:=FALSE;
   FOR i IN 1..length(punctarray) LOOP 
      FOR j IN 1..m LOOP 
         IF substr(password,j,1) = substr(punctarray,i,1) THEN
            ispunct:=TRUE;
             GOTO endsearch;
         END IF;
      END LOOP;
   END LOOP;
   IF ispunct = FALSE THEN
      raise_application_error(-20003, 'Password should contain at least one \
              digit, one character and one punctuation');
   END IF;

   <<endsearch>>
   -- Check if the password differs from the previous password by at least
   -- 3 letters
   IF old_password IS NOT NULL THEN
     differ := length(old_password) - length(password);

     IF abs(differ) < 3 THEN
       IF length(password) < length(old_password) THEN
         m := length(password);
       ELSE
         m := length(old_password);
       END IF;

       differ := abs(differ);
       FOR i IN 1..m LOOP
         IF substr(password,i,1) != substr(old_password,i,1) THEN
           differ := differ + 1;
         END IF;
       END LOOP;

       IF differ < 3 THEN
         raise_application_error(-20004, 'Password should differ by at \
         least 3 characters');
       END IF;
     END IF;
   END IF;
   -- Everything is fine; return TRUE ;   
   RETURN(TRUE);
END;
/



ALTER PROFILE DEFAULT LIMIT
PASSWORD_LIFE_TIME 60
PASSWORD_GRACE_TIME 10
PASSWORD_REUSE_TIME 1800
PASSWORD_REUSE_MAX UNLIMITED
FAILED_LOGIN_ATTEMPTS 3
PASSWORD_LOCK_TIME 1/1440
PASSWORD_VERIFY_FUNCTION verify_function;