[CPDEV-96114] add keepalived globals and custom template support

[Imadzuma]

Description

Now it's not possible to provide additional parameters for keepalived configuration except vrrp_ips.
But in fact, user should sometimes specify some custom parameters related to their environment, e.g.: https://serverfault.com/questions/821809/keepalived-send-gratuitous-arp-periodically/822004#822004

Fixes # (issue)

Solution

• Added new services.loadbalancer.keepalived.global section for global_defs keepalived parameters. Now following parameters are supported here:
  • vrrp_garp_master_refresh;
• Modified keepalived config generation to support common parameters, not related to specific vrrp-ip;
• Supported user specified config or config_file as for haproxy configuration;
• Added documentation section with the list of parameters that are used for keepalived configuration;

Test Cases

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration.

TestCase 1: custom vrrp_garp_master_refresh value

Test Configuration:

• Hardware:
• OS:
• Inventory: custom vrrp_garp_master_refresh (e.g. 10) specified;

Steps:

1. Run kubemarine install;
2. Run sudo tcpdump -i <interface> -nn arp on some node;

Results:

Before	After
Installation task fails, if schema validation is enabled	Successful installation
No global_defs section in /etc/keepalived/keepalived.conf on balancers	global_defs section with vrrp_garp_master_refresh specified in /etc/keepalived/keepalived.conf on balancers
tcpdump handles garp requests only when vrrp ip changes the node	tcpdump handles garp request for vrrp every 10 seconds (or other time, specified in vrrp_garp_master_refresh`)

TestCase 2: custom config value

Test Configuration:

• Hardware:
• OS:
• Inventory: custom config specified for keepalived;

Steps:

1. Run kubemarine install;

Results:

Before	After
Installation task fails, if schema validation is enabled	Successful installation
Default keepalived configuraiton /etc/keepalived/keepalived.conf on balancers	custom configuration in /etc/keepalived/keepalived.conf on balancers

TestCase 3: custom config_file value

Test Configuration:

• Hardware:
• OS:
• Inventory: custom config_file specified for keepalived;

Steps:

0. Create custom keepalived template, based on default one. Add vrrp_garp_master_refresh_repeat parameter in global_def section with 5 value.
1. Run kubemarine install;
2. Run sudo tcpdump -i <interface> -nn arp on some node;

Results:

Before	After
Installation task fails, if schema validation is enabled	Successful installation
No vrrp_garp_master_refresh_repeat in /etc/keepalived/keepalived.conf on balancers	custom vrrp_garp_master_refresh_repeat in /etc/keepalived/keepalived.conf on balancers
tcpdump handles garp requests only when vrrp ip changes the node	tcpdump handles 5 garp requests for vrrp every 10 seconds (or other time, specified in vrrp_garp_master_refresh`)

TestCase 4: keep_config_updated=False case

Test Configuration:

• Hardware:
• OS:
• Inventory: inentory with services.loadbalancer.keepalived.keep_config_updated=False property

Steps:

1. Run kubemarine install --tasks prepare,deploy.loadbalancer;
2. Check keepalived configuration;

Results:

Before	After
Keepalived configured by kubemaine	keepalived is not configured

Checklist

• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• Integration CI passed
• Unit tests. If Yes list of new/changed tests with brief description
• There is no merge conflicts

Unit tests

Indicate new or changed unit tests and what they do, if any.

[OleksandrIaresko]

QA Regression cases were tested/passed
Functional cases are in progress...

[koryaga]

@shmo1218 pls update