Creating CSR with multiple Domains With Openssl

Creating a CSR (Certificate Signing Request) with multiple domains using OpenSSL involves generating a private key and a CSR file, which includes the details of the domain(s) to be included in the certificate. The process involves the following steps:

Generate a private key using the openssl command with the following syntax:

openssl genrsa -out domain.key 2048

This generates a private key file named "domain.key" with 2048 bits of encryption.

Create a configuration file (e.g. domain.conf) that contains the details of the domains to be included in the certificate. This file should contain the following details:

[req]

default_bits       = 2048

default_keyfile    = domain.key

distinguished_name = req_distinguished_name

req_extensions     = req_ext

[req_distinguished_name]

countryName             = Country Name (2 letter code)

stateOrProvinceName     = State or Province Name (full name)

localityName            = Locality Name (eg, city)

organizationName        = Organization Name (eg, company)

commonName              = Common Name (e.g. server FQDN or YOUR name)

emailAddress            = Email Address

[req_ext]

subjectAltName          = @alt_names

[alt_names]

DNS.1                  = example.com

DNS.2                  = www.example.com

DNS.3                  = subdomain.example.com

In the example above, "example.com", "www.example.com", and "subdomain.example.com" are included as the alternate domain names.

Generate a CSR file using the openssl command with the following syntax:

openssl req -new -sha256 -key domain.key -out domain.csr -config domain.conf

This generates a CSR file named "domain.csr" that contains the details of the private key and the alternate domain names specified in the configuration file.

Submit the CSR file to a Certificate Authority (CA) to obtain a signed SSL certificate that can be installed on the server.

Overall, this process allows for the creation of a CSR file with multiple domain names that can be used to obtain a signed SSL certificate to secure those domains.

docker: 'stack' is not a docker command.

The error message "docker: 'stack' is not a docker command" suggests that the version of Docker being used does not support the "stack" command. The solution to this problem is to upgrade Docker to version 1.13 or higher. In the given example, the solution is to upgrade Docker to version 1.13 by downloading the required RPM packages from the Docker project repository and installing them using the "rpm -i" command. After the installation, the "systemctl enable docker" and "systemctl start docker" commands are used to enable and start the Docker service.While deploying the docker services using stack deploy command. We got following error.

docker stack deploy -c docker-compose.yml appslab

docker: 'stack' is not a docker command.
See 'docker --help'.

Resolution
Upgrade docker to 1.13

In Centos 7 we used the following to get the docker upgraded. Now the docket-latest package in centos7 is upgraded to 1.13

wget https://yum.dockerproject.org/repo/main/centos/7/Packages/docker-engine-1.13.1-1.el7.centos.x86_64.rpm
wget https://yum.dockerproject.org/repo/main/centos/7/Packages/docker-engine-selinux-1.13.1-1.el7.centos.noarch.rpm

#package for docker-engine-selinux

yum install -y policycoreutils-python
rpm -i docker-engine-selinux-1.13.1-1.el7.centos.noarch.rpm

#package for docker-engine

yum install -y libtool-ltdl libseccomp
rpm -i docker-engine-1.13.1-1.el7.centos.x86_64.rpm

#remove rpm packages

rm docker-engine-* -f

#enable systemd service

systemctl enable docker

#start docker

systemctl start docker

Fedora 26 + Virtualbox 5.1 + kenel 4.12

Upgrading your virtual machine (VM) environment can sometimes lead to unexpected issues. A common problem users might encounter after upgrading VirtualBox is the VM failing to start. In this post, we'll walk through a specific error and provide a step-by-step guide to resolve it, ensuring your virtual environment gets back up and running smoothly.

Understanding the Error

Upon attempting to start a VM after an upgrade, you might encounter an error in your logs similar to this:

/tmp/vbox.0/r0drv/linux/memuserkernel-r0drv-linux.o: warning: objtool: .fixup: unexpected end of section
if [ "-pg" = "-pg" ]; then if [ /tmp/vbox.0/r0drv/linux/memuserkernel-r0drv-linux.o != "scripts/mod/empty.o" ]; then ./scripts/recordmcount "/tmp/vbox.0/r0drv/linux/memuserkernel-r0drv-linux.o"; fi; fi;
make[1]: *** [Makefile:1519: _module_/tmp/vbox.0] Error 2
make: *** [Makefile:304: vboxdrv] Error 2

This error typically indicates a problem with the VirtualBox kernel modules not compiling or loading correctly due to incompatibilities or issues within the system.

Step-by-Step Solution

Fear not, as this issue can often be resolved by applying a patch to the VirtualBox source. Here's how you can fix it:

1. Change to the VirtualBox Source Directory:

Navigate to the directory where VirtualBox sources are stored:

cd /usr/share/virtualbox/src

2. Obtain the Necessary Patch:

Download the patch designed to fix the issue:

sudo wget http://paste.siduction.org/20170629003423

3. Apply the Patch:

Apply the downloaded patch to the VirtualBox source:

sudo patch -Np0 < 20170629003423

4. Reconfigure VirtualBox:

After applying the patch, you need to reconfigure VirtualBox to make sure it recognizes the changes:

/sbin/vboxconfig

Post-Solution Tips:

Have Fun! Now that you've resolved the issue, your VMs should start as expected. Dive back into your virtual environment and continue your work or play.

Stay Updated: Keep your system and VirtualBox updated to avoid similar issues in the future. Developers regularly release patches and updates to address known bugs and compatibility issues.

Seek Community Help: If you encounter further issues or the problem persists, don't hesitate to seek help from the VirtualBox community forums or check out other user experiences for additional insights.

Conclusion

Encountering errors after a system or software upgrade can be frustrating, but with the right approach and resources, most issues can be resolved. By understanding the error, carefully following the provided steps, and engaging with the community, you can overcome challenges and enjoy a seamless virtualization experience with VirtualBox. Keep exploring, learning, and sharing your knowledge with others!

Minio Running as Service

Minio is a distributed object storage server, similar to Amazon S3, that allows you to store and access large amounts of data. Since the service is running on different hosts, it is important to have a shared storage mechanism so that the data is synchronized across all nodes. To achieve this, a bind mount is used to mount a directory on the host machine to the Minio server container, allowing it to read and write data to the directory. Additionally, two Docker secrets are created for access and secret keys to authenticate and authorize access to the Minio server. Finally, the service is created with the docker service create command, specifying the name of the service, the port to publish, the constraint to run the service only on a manager node, the bind mount for data synchronization, and the two Docker secrets for authentication. The minio/minio image is used to run the Minio server, and the /data directory is specified as the location to store data.

echo "AKIAIOSFODNN7EXAMPLE" | docker secret create access_key -
echo "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY" | docker secret create secret_key -

docker service create --name="minio-service" --publish 9000:9000   --constraint 'node.role == manager' --mount type=bind,src=/mnt/minio/,dst=/data --secret="access_key" --secret="secret_key" minio/minio server /data

Minio: S3 Compatible Stoage in Docker

Minio is a distributed object storage server that is designed to be scalable and highly available. It is built for cloud-native applications and DevOps. Minio provides Amazon S3 compatible API for cloud-native applications to store and retrieve data. It is open-source and can be deployed on-premise, on the cloud or on Kubernetes.

The command docker pull minio/minio pulls the Minio image from Docker Hub. The command docker run -p 9000:9000 minio/minio server /data runs a Minio container with port forwarding from the host to the container for the Minio web interface. The /data parameter specifies the path to the data directory that will be used to store the data on the container's file system.

**We need to have the docker env up and running.

docker pull minio/minio
docker run -p 9000:9000 minio/minio server /data

After running this command, you can access the Minio web interface by navigating to http://localhost:9000 in your web browser.

Inceass the Root Disk Size for Centos in Aws

Issue: Root Partition not scaled after EBS is resized.

Growpart called by cloud-init only works for kernels >3.8. Only newer kernels support changing the partition size of a mounted partition. When using an older kernel the resizing of the root partition happens in the initrd stage before the root partition is mounted and the subsequent cloud-init growpart run is a no-op.

#lsblk
NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvda    202:0    0  30G  0 disk
└─xvda1 202:1    0   8G  0 part /
Perform the following command as root:

# yum install cloud-utils-growpart

# growpart /dev/xvda 1

# reboot
After the reboot:

# lsblk
NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvda    202:0    0  30G  0 disk
└─xvda1 202:1    0  30G  0 part /

Qubole : Load Multiple tables to Qubole Hive table from a Data Store

API call to Load Multiple tables from a Qubole Data Store to Hive table. 

[rahul@local qubole]$ cat /databasescript 

#!/bin/bash

#Qubole API Key

AUTH="***********"

#Database Name

DB_NAME="***********"

#Host Name

DB_HOST="***********"

#User Name

DB_USER="***********

#Password 

DB_PASS='***********'

echo $DB_PASS

## request table import from tap;

function tableImport() {

request_body=$(cat <<EOF

{

   "command_type":"DbImportCommand",

   "mode":"1",

   "hive_serde":"orc",

   "hive_table":"<HIVE TABLE NAME>.$1",

   "dbtap_id":"$2",

   "db_table":"$1",

   "db_parallelism":"1",

   "use_customer_cluster":"1",

   "customer_cluster_label":"Qubole_Data_Import",

   "tags":[" Data"]

}

EOF

)

echo $request_body

   curl -X POST \

-H "X-AUTH-TOKEN: $AUTH" \

-H "Content-Type:application/json" \

-d "$request_body" https://api.qubole.com/api/v1.2/commands/

}

##register database with tap

request_body=$(cat <<EOF

{

  "db_name":"$DB_NAME",

  "db_host":"$DB_HOST",

  "db_user":"$DB_USER",

  "db_passwd":"$DB_PASS",

  "db_type":"sqlserver",

  "db_location":"on-premise",

  "gateway_ip": "***********",

  "gateway_port": "***********",

  "gateway_username": "***********",

  "gateway_private_key": "***********"}

EOF

)

echo $KEY

ID=$(curl -s -X POST \

-H "X-AUTH-TOKEN: $AUTH" \

-H "Content-Type:application/json" \

-d "$request_body" https://api.qubole.com/api/v1.2/db_taps/ | jq .id)

#get the tables and call import

curl -s -H "X-AUTH-TOKEN: $AUTH" \

     -H "Content-Type:application/json" \

     https://api.qubole.com/api/v1.2/db_taps/$ID/tables | jq -r .[] | while read x; do  tableImport $x $ID; done

# can't delete the tap at the end unless we continuously poll for no active jobs;

STATUS="null"

while [ "$STATUS" = "null" ]

do

STATUS=$(curl  -s -X DELETE \

 -H "X-AUTH-TOKEN: $AUTH" \

 -H "Content-Type:application/json" \

 https://api.qubole.com/api/v1.2/db_taps/$ID | jq .status)

echo -n "."

sleep 5

done