ControlNetworkGuru does not take into account custom CIDR when assigning System VM link local IP address

[Rubueno]

ISSUE TYPE

• Bug Report

COMPONENT NAME

Management, Network, SystemVM

CLOUDSTACK VERSION

4.16.1

CONFIGURATION

In database:

MariaDB [cloud]> select name,value from configuration where name = 'control.cidr';
+--------------+------------------+
| name         | value            |
+--------------+------------------+
| control.cidr | 169.254.240.0/20 |
+--------------+------------------+
MariaDB [cloud]> select name,value from configuration where name = 'control.gateway';
+-----------------+---------------+
| name            | value         |
+-----------------+---------------+
| control.gateway | 169.254.240.1 |
+-----------------+---------------+
MariaDB [cloud]> select count(*) from op_dc_link_local_ip_address_alloc;
+----------+
| count(*) |
+----------+
|    65533 |
+----------+

On agent:

root@hv-04-02-21:~# grep control.cidr /etc/cloudstack/agent/agent.properties
control.cidr=169.254.240.0/20

SUMMARY

When having set a control.cidr different from the norm (168.254.0.0/16) and the database table op_dc_link_local_ip_address_alloc is already populated with all the addresses in the default CIDR, then allocating an IP to a System VM does not take into account the requested CIDR, thus allocating an IP address in the wrong range.

https://github.com/apache/cloudstack/blob/main/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterLinkLocalIpAddressDaoImpl.java#L52 should take this into account. This function is called in https://github.com/apache/cloudstack/blob/main/server/src/main/java/com/cloud/network/guru/ControlNetworkGuru.java#L134

STEPS TO REPRODUCE

• Install new management server
• After kickstart, disable the zone to prevent any system vm deploys
• In mysql database: select count(*) from op_dc_link_local_ip_address_alloc;, it would return 65533
• Connect agents
• Configure control.cidr on the manager and agents, and control.gateway on the manager, ie:

control.cidr=169.254.240.0/20
control.gateway=169.254.240.1

• Enable the zone, check the system vm link local address

EXPECTED RESULTS

• The System VMs should receive an IP address in the configured CIDR.
• Additional expected: In mysql database: select count(*) from op_dc_link_local_ip_address_alloc;, it should return 4093

ACTUAL RESULTS

• System VMs receive an IP address in the default 169.254.0.0/16 range

2022-09-07 22:45:35,338 DEBUG [o.a.c.e.o.NetworkOrchestrator] (Work-Job-Executor-3:ctx-b1c76634 job-149/job-150 ctx-224681ec) (logid:32608415) Network id=201 is already implemented
2022-09-07 22:45:35,524 DEBUG [c.c.n.g.ControlNetworkGuru] (Work-Job-Executor-3:ctx-b1c76634 job-149/job-150 ctx-224681ec) (logid:32608415) Reserved NIC for v-18-VM [ipv4:169.254.167.69 netmask:255.255.240.0 gateway:169.254.240.1]