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Add markdown linting support

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David Young
2021-10-20 15:25:05 +13:00
committed by GitHub
parent 938d4c7f3b
commit 64a76273c1
127 changed files with 655 additions and 1348 deletions
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19
manuscript/ha-docker-swarm/keepalived.md
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@@ -34,7 +34,7 @@ On all nodes which will participate in keepalived, we need the "ip_vs" kernel mo
Set this up once-off for both the primary and secondary nodes, by running:
```
```bash
echo "modprobe ip_vs" >> /etc/modules
modprobe ip_vs
```
@@ -43,14 +43,13 @@ modprobe ip_vs
Assuming your IPs are as follows:
```
* 192.168.4.1 : Primary
* 192.168.4.2 : Secondary
* 192.168.4.3 : Virtual
```
- 192.168.4.1 : Primary
- 192.168.4.2 : Secondary
- 192.168.4.3 : Virtual
Run the following on the primary
```
```bash
docker run -d --name keepalived --restart=always \
--cap-add=NET_ADMIN --cap-add=NET_BROADCAST --cap-add=NET_RAW --net=host \
-e KEEPALIVED_UNICAST_PEERS="#PYTHON2BASH:['192.168.4.1', '192.168.4.2']" \
@@ -60,7 +59,8 @@ docker run -d --name keepalived --restart=always \
```
And on the secondary[^2]:
```
```bash
docker run -d --name keepalived --restart=always \
--cap-add=NET_ADMIN --cap-add=NET_BROADCAST --cap-add=NET_RAW --net=host \
-e KEEPALIVED_UNICAST_PEERS="#PYTHON2BASH:['192.168.4.1', '192.168.4.2']" \
@@ -73,7 +73,6 @@ docker run -d --name keepalived --restart=always \
That's it. Each node will talk to the other via unicast (*no need to un-firewall multicast addresses*), and the node with the highest priority gets to be the master. When ingress traffic arrives on the master node via the VIP, docker's routing mesh will deliver it to the appropriate docker node.
## Summary
What have we achieved?
@@ -88,4 +87,4 @@ What have we achieved?
[^1]: Some hosting platforms (*OpenStack, for one*) won't allow you to simply "claim" a virtual IP. Each node is only able to receive traffic targetted to its unique IP, unless certain security controls are disabled by the cloud administrator. In this case, keepalived is not the right solution, and a platform-specific load-balancing solution should be used. In OpenStack, this is Neutron's "Load Balancer As A Service" (LBAAS) component. AWS, GCP and Azure would likely include similar protections.
[^2]: More than 2 nodes can participate in keepalived. Simply ensure that each node has the appropriate priority set, and the node with the highest priority will become the master.
--8<-- "recipe-footer.md"
--8<-- "recipe-footer.md"