Scheduling backups in a remote server

This page describes how to schedule backups for Cassandra without the Cloud Storage. In this method, backups are stored on a remote server specified by you instead of a Cloud Storage bucket. Apigee uses SSH to communicate with the remote server.

You must schedule the backups as cron jobs. Once a backup schedule has been applied to your hybrid cluster, a Kubernetes backup job is periodically executed according to the schedule in the runtime plane. The job triggers a backup script on each Cassandra node in your hybrid cluster that collects all the data on the node, creates an archive (compressed) file of the data, and sends the archive to the server specified in your overrides.yaml file.

The following steps include common examples for completing specific tasks, like creating an SSH key pair. Use the methods that are appropriate to your installation.

The procedure has the following parts:

Set up the server and SSH
Set the schedule and destination for backup

Set up the server and SSH

Select a Backup Server: Choose a Linux or Unix server with adequate storage for your backups and ensure it can be accessed via SSH from your Apigee hybrid runtime plane.
Configure the SSH Server: Either install an SSH server or confirm that an existing one is secure.

Create an SSH Key Pair: Generate an SSH key pair without a passphrase:For example:

ssh-keygen -t rsa -b 4096 -C exampleuser@example.com
  Enter file in which to save the key (/Users/exampleuser/.ssh/id_rsa): $APIGEE_HOME/hybrid-files/certs/ssh_key
  Enter passphrase (empty for no passphrase):
  Enter same passphrase again:
  Your identification has been saved in ssh_key
  Your public key has been saved in ssh_key.pub
  The key fingerprint is:
  SHA256:DWKo334XMZcZYLOLrd/8HNpjTERPJJ0mc11UYmrPvSA exampleuser@example.com
  The key's randomart image is:
  +---[RSA 4096]----+
  |          +.  ++X|
  |     .   . o.=.*+|
  |    . o . . o==o |
  |   . . . =oo+o...|
  |  .     S +E oo .|
  |   . .   .. . o .|
  |    . . .  . o.. |
  |     .  ...o ++. |
  |      .. .. +o+. |
  +----[SHA256]-----+

Where: exampleuser@example.com is a string. Any string that follows -C in the ssh-keygen command becomes a comment included in the newly created ssh key. The input string can be any string. When you use an account name in the form of exampleuser@example.com, you can quickly identify which account goes with the key.

The command will generate two SSH key files, A private key file (for example `ssh_key.rsa`) and a public key file (for example, `ssh_key.pub`).

Save the private key to a location that your runtime plane can access.

Add a User Account: On the backup server, create a user named apigee with a home directory under /home/apigee. Make sure the new apigee user has a home directory under /home.
Set Up the .ssh Directory: On the backup server, create a .ssh directory in /home/apigee/.ssh. For example:
```
cd /home/apigee
      mkdir .ssh
      cd .ssh
      vi authorized_keys
```
Install the Public Key: Place the public key into the authorized_keys file within the /home/apigee/ directory. The backup directory can be any directory as long as the apigee user has access to it.Paste the contents of the ssh public key file into the file.
Verify SSH Access: Test the connection from your local machine or a cluster node:

ssh -i PATH_TO_PRIVATE_KEY_FILE apigee@BACKUP_SERVER_IP

Set the schedule and destination for backup

You set the schedule and destination for backups in your overrides.yaml file.

Add the following parameters to your overrides.yaml file:

Parameters

cassandra:
  backup:
    enabled: true
    keyFile: "PATH_TO_PRIVATE_KEY_FILE"
    server: "BACKUP_SERVER_IP"
    storageDirectory: "/home/apigee/BACKUP_DIRECTORY"
    cloudProvider: "HYBRID" # required verbatim "HYBRID" (all caps)
    schedule: "SCHEDULE"

Example

cassandra:
  backup:
    enabled: true
    keyFile: "private.key" # path relative to apigee-datastore path
    server: "34.56.78.90"
    storageDirectory: "/home/apigee/cassbackup"
    cloudProvider: "HYBRID"
    schedule: "0 2 * * *"

Where:

Property	Description
`backup:enabled`	Backup is disabled by default. You must set this property to `true`.
`backup:keyFile`	`PATH_TO_PRIVATE_KEY_FILE` The path on your local file system to the SSH private key file (named `ssh_key` in the step where you created the SSH key pair). This path must be relative to the `apigee-datastore` chart directory.
`backup:server`	`BACKUP_SERVER_IP` The IP address of your backup server.
`backup:storageDirectory`	`BACKUP_DIRECTORY` The name of the backup directory on your backup server. This must be a directory within `home/apigee` (the backup directory is named `cassandra_backup` in the step where you created the backup directory).
`backup:cloudProvider`	`GCP/HYBRID` For a Cloud Storage backup, set the property to `GCP`. For example, `cloudProvider: "GCP"`. For a remote server backup, set the property to `HYBRID`. For example, `cloudProvider: "HYBRID"`.
`backup:schedule`	`SCHEDULE` The time when the backup starts, specified in standard crontab syntax. Times are in the local time zone of the Kubernetes cluster. Default: `0 2 * * ` Note:* Avoid scheduling a backup that starts a short time after you apply the backup configuration to your cluster. When you apply the backup configuration, Kubernetes recreates the Cassandra nodes. If the backup starts before the nodes restart, the first backup will fail and the subsequent backups will pass.

Apply the backup configuration to the storage scope of your cluster:
```
helm upgrade datastore apigee-datastore/ \
  --namespace apigee \
  --atomic \
  -f OVERRIDES_FILE.yaml
```
Note: If you see an error saying Error: UPGRADE FAILED: "datastore" has no deployed releases, replace upgrade with install and try the command again.

Where OVERRIDES_FILE is the path to the overrides file you just edited.

Verify the backup job. For example:

kubectl get cronjob -n apigee

NAME                      SCHEDULE     SUSPEND   ACTIVE   LAST SCHEDULE   AGE
apigee-cassandra-backup   33 * * * *   False     0        <none>          94s

Troubleshooting

Test the connection from a Cassandra pod. You need to make sure that your Cassandra pods can connect to your backup server using SSH:
1. Log into the shell of your Cassandra pod. For example:
```
kubectl exec -it -n apigee APIGEE_CASSANDRA_DEFAULT_0 -- /bin/bash
```
  Where APIGEE_CASSANDRA_DEFAULT_0 is the name of a Cassandra pod. Change this to the name of the pod you want to connect from.
2. Connect by SSH to your backup server, using the private SSH key mounted the Cassandra pod and server IP address:
```
ssh -i /var/secrets/keys/key apigee@BACKUP_SERVER_IP
```
  Note: You may see a warning at this point saying your server's fingerprint is unrecognized and asks if you would like to continue. You can continue at that prompt and verify the SSH configuration.
If you have problems accessing your remote server from the Cassandra pod, please check your ssh configuration on the remote server again and also make sure that upgrading the datastore was successful.
You can check if Cassandra uses the correct private key by running the following command while you are logged in to your Cassandra pod, and compare the output with the private key you created:
```
cat /var/secrets/keys/key
```