Implementing security group rules
In the following example, an instance named WEB1
will be created that acts as a web server running Apache on ports 80
and 443
. To demonstrate how security group rules are implemented on a compute node, take note of the following WEB_SERVERS
security group created with the Neutron security-group-create
command:
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Figure 6.3
The following screenshot shows two security group rules being added to the WEB_SERVERS
security group using the security-group-rule-create
command. The rules allow inbound connections on ports 80
and 443
from any remote host:
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Figure 6.4
Using the Neutron port-update
command, the WEB_SERVERS
security group can be applied to the Neutron port of the WEB1
instance, as shown in the following screenshot:
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Figure 6.5
Once a security group is applied to the corresponding Neutron port of an instance, a series of iptables rules and chains are implemented on the compute node hosting the instance.
Stepping through the chains
The implementation of security group...