Skip to main content

Dell Vostro 1520 Boot problem, Recovering & restore Grub from a live Ubuntu cd.

In Vostro 1520 Dell Laptop series, when Ubuntu installed with windows (Dual Boot), due to a problem in bios the MBR will get corrupted and after that you will be unable to see the Grub loader at the startup and you want be able to load either windows or Ubuntu.
This happens only because of the corruption at MBR record or partition table. 
So by reinstalling grub to the partition u can resolve this problem. The steps of resolving are given below.


  1. First you have to boot from the Ubuntu Live CD
  2. Then you have to find the sd number of the partition that grub is installed in. ( If you have a separate /boot partition it should be the boot partition sd number otherwise it should be the Ubuntu file system sd number. ). And here I assume that sd number is x.
  3. Open the Terminal and execute following codes
  4. sudo mkdir /mnt/root -- Setup a folder before change root.
  5. Using this code Mount the partition in to the folder created.
    • sudo mount -t ext3 /dev/sdax /mnt/root
  6. Mount and bind necessary places using following code
  7. Run this if /mnt/root/proc and /mnt/root/dev doesn't exist
    • sudo mkdir /mnt/root/proc
    • sudo mkdir /mnt/root/dev
  8. sudo mount -t proc none /mnt/root/proc
  9. sudo mount -o bind /dev /mnt/root/dev
  10. Now change the root to the configured folder using this code
      • sudo chroot /mnt/root /bin/bash 
    1. Install the grub to specified device.
      • grub-install /dev/sdax
    2. Now you are done. Restart and check.
    You will see that the grub is loading. Good luck !!!

    Comments

    Popular posts from this blog

    Generate JWT access tokens from WSO2 Identity Server

    In Identity Server 5.2.0 we have created an interface to generate access tokens. Using that we have developed a sample to generate JWT tokens. You can find that sample under msf4j samples[1][2]. If you are build it as it is you will need to use Java 8 to build since msf4j is developed on Java 8. So you will need to run Identity Server on Java 8 as well. After building the project[2] please copy the jar inside target directory to $IS_HOME/repository/components/dropins/ directory. And then please add the following configuration to Identity.xml which is placed under $IS_HOME/repository/conf/identity/ folder inside tag OAuth . <IdentityOAuthTokenGenerator>com.wso2.jwt.token.builder.JWTAccessTokenBuilder</IdentityOAuthTokenGenerator> Then go to the database you used to store oauth tokens (This is the database pointed from the datasource you mentioned in the $IS_HOME/repository/conf/identity/identity.xml) and then alter the size of the column ACCESS_TOKEN of the tab

    Oauth custom basic authenticator with WSO2 IS 5.1.0

    WSO2 Identity Server supports Oauth2 authorization code grant type with basic authentication OOTB. But basic authentication is done only with WSO2 user store. So there could be use cases that basic authentication has to be done against some other system. In this case you follow below steps to achieve your requirement. First you need to create an class which extends AbstractApplicationAuthenticator and implements LocalApplicationAuthenticator. Because this class is going to act as your application authenticator so it needs to be an implementation of application authenticator interface and to achieve this it needs to be a local authenticator as well. [2] public class CustomBasicAuthenticator extends AbstractApplicationAuthenticator implements LocalApplicationAuthenticator {   Then you need to override the initiateAuthenticationRequest method so you can redirect to the page to enter user and password. In my sample I redirected to the page that is used by our default basic au

    Integrate New Relic with WSO2 API Manager

    In WSO2 API Manager, we have two transports. HTTP servlet transport and Passthru / NIO transport. All the web application requests are handled through HTTP servlet transport which is on 9763 port and 9443 port with ssl and here we are using tomcat inside WSO2 products. All the service requests are served via Passthru / NIO transport which is on 8082 and 8243 with ssl. When we integrate API Manager with new relic in the way discussed in blog posts [5],[6], new relic only detects the calls made to tomcat transports. So we couldn’t get the API calls related data OOTB. But by further analyzing new relic APIs I managed to find a workaround for this problem. New relic supports publishing custom events via their insights api[1]. So what we can do is publish these data via custom API handler[2]. Following is a sample implementation of a handler that I used to test the scenario. I will attach the full project herewith[7]. I have created an osgi bundle with this implementation so after building