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Tag: Ubuntu

  • How to decode CSR (Certificate Signing Request) ?

    How to decode CSR (Certificate Signing Request) ?

    What is CSR?

    Certificate Signing Request
    Certificate Signing Request is encrypted piece of code which is going to used for generating the SSL Certificate for your domain name.

     

    CSR contains the information about Country, State, Location, Organisation Name, Common Name ie Domain Name , Email Address and Public Key.

    Lets see how to extract the information from the CSR file?

    How to extract information from the CSR?

    surya@x ~/ » openssl req -in blog.suryaelite.com.csr -text -noout

    How to verify the signature of CSR?

    surya@x ~/ » openssl req -in blog.suryaelite.com.csr -noout -verify

    To which company certificate is issued to?

    surya@x ~/ » openssl req -in blog.suryaelite.com.csr -noout -subject

    How to extract Public Key from CSR?

    surya@x ~/ » openssl req -in blog.suryaelite.com.csr -noout -pubkey

    This is how you can extract the various information from the CSR file.

  • AWS – NDB – Ubuntu – Add separate location for MySQL temporary (tmp) storage

    AWS – NDB – Ubuntu – Add separate location for MySQL temporary (tmp) storage

    aws_mysql_disk_addition

    By default MySQL uses the system default location used for temporary file storage, which is usually /tmp, /var/tmp, or /usr/tmp. In Ubuntu its /tmp. It’s good practice to specify separate location for MySQL, if you want to prevent System restart. If tmp location is on separate location then only MySQL restart will needed in case of any disk increase needed in future.

    Step 1: Create new EBS Volume by Login to Console and Click on EC2 Dashboard, then click on “Volumes”

    Step 2: Fill the details of Volume and click on create and the new Volume will be created within few seconds.

     

    Step 3: Attach the newly created volume to the Instance.

    Step 4: Check if the volume is attached or not by going to EC2 dashboard and clicking on that particular instance. You can also check by going to Volume stats as well.

    Step 5: Login to machine by your key or password.

    Step 6: Format Volume to ext4 and then mount it and make fstab entry as well.

    root@x:/mnt: lsblk
NAME    MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
xvda    202:0    0    40G  0 disk 
└─xvda1 202:1    0    40G  0 part /
xvdb    202:16   0   400G  0 disk /mnt/data
xvdf    202:80   0   200G  0 disk 


root@x: mkfs.ext4 /dev/xvdf
mke2fs 1.42.9 (4-Feb-2014)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
13107200 inodes, 52428800 blocks
2621440 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
1600 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks: 
    32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 
    4096000, 7962624, 11239424, 20480000, 23887872

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done     


root@x: mkdir /mnt/xvdf
root@x:/mnt: sudo mount /dev/xvdf /mnt/xvdf/
root@x: mkdir /mnt/xvdf/tmp_mysql
root@x:/mnt/xvdf# chown -Rf mysql:mysql /mnt/xvdf/tmp_mysql
root@x:/var: ln -s /mnt/xvdf/tmp_mysql/ /var/tmp_mysql

    Step 7: Now put the tmp_dir setting in /etc/my.cnf

    [mysqld]
tmpdir = /var/tmp_mysql

    Step 8: Restart the MySQL and check for setting by Login to MySQL and executing below mentioned Query

    root@x:/: sudo service mysql restart

     

    mysql> SHOW VARIABLES LIKE 'tmpdir';

    This is how you can change the temporary directory in AWS hosted Ubuntu Linux environment.

     

  • Ubuntu 16.04 – Cisco VPN Client installation

    Ubuntu 16.04 – Cisco VPN Client installation

    cisco_vpn_client

    On Ubuntu 14.04 only sudo apt-get install network-manager-vpnc was working. But for Ubuntu 16.04 you need to install network-manager-vpnc-gnome as well.

    Step 1: Open Terminal
    Step 2: run below command to install the cisco client

    sudo apt-get install network-manager-vpnc network-manager-vpnc-gnome

    Step 3: Click on the “Network Icon” on toolbar, then click “Edit Connections”
    Step 4: Click on “Add” Button
    Step 5: Choose “Cisco Compatible VPN (vpnc)”, click on “Create”
    Step 6: Fill the below details on VPN Tab

    • Gateway: VPN IP 199.229.XXX.XXX
      UserName
    • UserPassword
    • GroupName
    • GroupPassword

    Step 7: Click on Save

    VPN Setup has been completed.

    To connect VPN, click on the Network Icon on toolbar. Click on VPN Connections. Choose the VPN which you have recently created.

    Please make sure, you are on different network to connect VPN.

  • Solution – Apache – SoftException in Application.cpp:388: GID of script “index.php” is smaller than min_gid error

    Solution – Apache – SoftException in Application.cpp:388: GID of script “index.php” is smaller than min_gid error

    apache 500 error

    If you are getting the errors in apache logs like below in cPanel/WHM web hosting

    Error: Apache – SoftException in Application.cpp:388: GID of script “index.php”

    [Mon Oct 02 08:29:33.684683 2017] [core:error] [pid 24787:tid 140323590199040] [client 91.73.173.118:50064] End of script output before headers: index.php
[Mon Oct 02 08:29:34.812915 2017] [:error] [pid 9068:tid 140323474810624] [client 91.73.173.118:50065] SoftException in Application.cpp:388: GID of script "/index.php" is smaller than min_gid
[Mon Oct 02 08:29:34.812981 2017] [core:error] [pid 9068:tid 140323474810624] [client 91.73.173.118:50065] End of script output before headers: index.php
[Mon Oct 02 08:29:34.817808 2017] [:error] [pid 9068:tid 140323474810624] [client 91.73.173.118:50065] SoftException in Application.cpp:388: GID of script "index.php" is smaller than min_gid

    most probably the file user or group ownership has been changed of that file to root.

    root@x.com [directory]# ls -lrt | grep "index.php"
total 48000

-rw-r--r-- 1 abc_user root         1782 Oct  2 07:10 index.php

    Now change the ownership  back to current user is the fix

    Solution: Change the Ownership of file to the  ‘username’ where public_html folder is present.

    Like in /home/abc_user/public_html/ the user will be ‘abc_user‘

    root@x.com [directory]# sudo chown abc_user:abc_user index.php

    This is how you can fix above mentioned problem.

    The above fix will also work for below mentioned error

    Error : Apache Mismatch between target GID (501) and GID (99) of file “index.php”

    [Mon Oct 02 08:30:52.056769 2017] [core:error] [pid 24787:tid 140323474810624] [client 91.73.173.118:51627] End of script output before headers: index.php
[Mon Oct 02 08:30:52.062511 2017] [:error] [pid 24787:tid 140323474810624] [client 91.73.173.118:51627] SoftException in Application.cpp:456: Mismatch between target GID (501) and GID (99) of file "index.php"
[Mon Oct 02 08:30:52.062577 2017] [core:error] [pid 24787:tid 140323474810624] [client 91.73.173.118:51627] End of script output before headers: index.php
[Mon Oct 02 08:30:54.060966 2017] [:error] [pid 24729:tid 140323464320768] [client 154.122.107.180:33276] SoftException in Application.cpp:456: Mismatch between target GID (501) and GID (99) of file "index.php", referer: http://m.facebook.com/