Redis Sentinel manual failover

Hint

You're not able to control which redis replica will chosen for the failover.

Have a look at the configured masters, current master and the available replicas

INFO sentinel

SENTINEL master <master name>
SENTINEL get-master-addr-by-name <master name> # IP and port only

SENTINEL slaves <master name>

Force a failover
```
SENTINEL failover <master name> 
```
After some seconds you can have a second look at the current master:
```
SENTINEL get-master-addr-by-name <master name> 
```
The IP should have changed.

Run multiple Redis servers on Ubuntu

This is a way to run multiple redis server on one ubuntu server.

Change some Variables.
From this:

DAEMON_ARGS=/etc/redis/redis.conf
NAM...

Create a 1 GB file to swap to (we have sufficient space on / on this machine. Use a different partition if necessary)

sudo dd if=/dev/zero of=/var/swapfile bs=1M count=1024

If you prefer 2GB swap, chose count=2048, 4GB: count=4096

C...

I'm creating certificate requests with this command:

openssl req -new -out www.example.com.csr -keyout www.example.com.key -newkey rsa:2048 -nodes

When I try to upload the certificate to AWS IAM I get this error:

$ aws iam upload-se...

Bash stores the exitcodestatus of piped commands in the environment variable PIPESTATUS

So you can just echo ${PIPESTATUS[@]} to get them all.

13:52:30 ✔ claus:~$ ps ax | grep /usr/bin/ruby
13205 pts/20   S+     0:00 grep --color=auto /...

We want to make the following firewall rule to be applyable to different network interfaces (for e.g. different environments) with just one variable:

firewall { "010-reject-port":
  ensure      => present,
  dport       => [ 80...

Claus-Theodor Riegg

Last edit

3 years ago

Andreas Vöst

Keywords

ops