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Posted to commits@cloudstack.apache.org by pr...@apache.org on 2013/01/11 13:44:01 UTC
git commit: Autoscale Documentation : Reviewed-By: Jessica Tomechak
Updated Branches:
refs/heads/master eb40d2337 -> 499c474ed
Autoscale Documentation : Reviewed-By: Jessica Tomechak
Project: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/commit/499c474e
Tree: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/tree/499c474e
Diff: http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/diff/499c474e
Branch: refs/heads/master
Commit: 499c474ed0123865f3f4feca5f6320ac322b6f37
Parents: eb40d23
Author: Radhika PC <ra...@citrix.com>
Authored: Fri Jan 11 17:53:09 2013 +0530
Committer: Pranav Saxena <pr...@citrix.com>
Committed: Fri Jan 11 17:53:09 2013 +0530
----------------------------------------------------------------------
docs/en-US/autoscale.xml | 284 +++++++++++++++
docs/en-US/configure-snmp-rhel.xml | 86 +++++
.../external-firewalls-and-load-balancers.xml | 43 ++-
...guration-of-external-firewalls-loadbalancer.xml | 46 +++
4 files changed, 440 insertions(+), 19 deletions(-)
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http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/499c474e/docs/en-US/autoscale.xml
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diff --git a/docs/en-US/autoscale.xml b/docs/en-US/autoscale.xml
new file mode 100644
index 0000000..d63281f
--- /dev/null
+++ b/docs/en-US/autoscale.xml
@@ -0,0 +1,284 @@
+<?xml version='1.0' encoding='utf-8' ?>
+<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
+%BOOK_ENTITIES;
+]>
+
+<!-- Licensed to the Apache Software Foundation (ASF) under one
+ or more contributor license agreements. See the NOTICE file
+ distributed with this work for additional information
+ regarding copyright ownership. The ASF licenses this file
+ to you under the Apache License, Version 2.0 (the
+ "License"); you may not use this file except in compliance
+ with the License. You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing,
+ software distributed under the License is distributed on an
+ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ KIND, either express or implied. See the License for the
+ specific language governing permissions and limitations
+ under the License.
+-->
+<section id="autoscale">
+ <title>Configuring AutoScale</title>
+ <para>AutoScaling allows you to scale your back-end services or application VMs up or down
+ seamlessly and automatically according to the conditions you define. With AutoScaling enabled,
+ you can ensure that the number of VMs you are using seamlessly scale up when demand increases,
+ and automatically decreases when demand subsides. Thus it helps you save compute costs by
+ terminating underused VMs automatically and launching new VMs when you need them, without the
+ need for manual intervention.</para>
+ <para>NetScaler AutoScaling is designed to seamlessly launch or terminate VMs based on
+ user-defined conditions. Conditions for triggering a scaleup or scaledown action can vary from a
+ simple use case like monitoring the CPU usage of a server to a complex use case of monitoring a
+ combination of server's responsiveness and its CPU usage. For example, you can configure
+ AutoScaling to launch an additional VM whenever CPU usage exceeds 80 percent for 15 minutes, or
+ to remove a VM whenever CPU usage is less than 20 percent for 30 minutes.</para>
+ <para>&PRODUCT; uses the NetScaler load balancer to monitor all aspects of a system's health and
+ work in unison with &PRODUCT; to initiate scale-up or scale-down actions. The supported
+ NetScaler version is 10.0.</para>
+ <formalpara>
+ <title>Prerequisites</title>
+ <para>Before you configure an AutoScale rule, consider the following:</para>
+ </formalpara>
+ <itemizedlist>
+ <listitem>
+ <para>Ensure that the necessary template is prepared before configuring AutoScale. When a VM
+ is deployed by using a template and when it comes up, the application should be up and
+ running.</para>
+ <note>
+ <para>If the application is not running, the NetScaler device considers the VM as
+ ineffective and continues provisioning the VMs unconditionally until the resource limit is
+ exhausted.</para>
+ </note>
+ </listitem>
+ <listitem>
+ <para>Deploy the templates you prepared. Ensure that the applications come up on the first
+ boot and is ready to take the traffic. Observe the time requires to deploy the template.
+ Consider this time when you specify the quiet time while configuring AutoScale.</para>
+ </listitem>
+ <listitem>
+ <para>The AutoScale feature supports the SNMP counters that can be used to define conditions
+ for taking scale up or scale down actions. To monitor the SNMP-based counter, ensure that
+ the SNMP agent is installed in the template used for creating the AutoScale VMs, and the
+ SNMP operations work with the configured SNMP community and port by using standard SNMP
+ managers. For example, see <xref linkend="configure-snmp-rhel"/> to configure SNMP on a RHEL
+ machine.</para>
+ </listitem>
+ <listitem>
+ <para>Ensure that the endpointe.url parameter present in the Global Settings is set to the
+ Management Server API URL. For example, http://10.102.102.22:8080/client/api. In a
+ multi-node Management Server deployment, use the virtual IP address configured in the load
+ balancer for the management server’s cluster. Additionally, ensure that the NetScaler device
+ has access to this IP address to provide AutoScale support.</para>
+ <para>If you update the endpointe.url, disable the AutoScale functionality of the load
+ balancer rules in the system, then enable them back to reflect the changes. For more
+ information see <xref linkend="update-autoscale"/></para>
+ </listitem>
+ <listitem>
+ <para>If the API Key and Secret Key are regenerated for an AutoScale user, ensure that the
+ AutoScale functionality of the load balancers that the user participates in are disabled and
+ then enabled to reflect the configuration changes in the NetScaler.</para>
+ </listitem>
+ <listitem>
+ <para>In an advanced Zone, ensure that at least one VM should be present before configuring a
+ load balancer rule with AutoScale. Having one VM in the network ensures that the network is
+ in implemented state for configuring AutoScale.</para>
+ </listitem>
+ </itemizedlist>
+ <formalpara>
+ <title>Configuration</title>
+ <para>Specify the following:</para>
+ </formalpara>
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="./images/autoscale-config.png"/>
+ </imageobject>
+ <textobject>
+ <phrase>autoscaleateconfig.png: Configuring AutoScale</phrase>
+ </textobject>
+ </mediaobject>
+ <itemizedlist>
+ <listitem>
+ <para><emphasis role="bold">Template</emphasis>: A template consists of a base OS image and
+ application. A template is used to provision the new instance of an application on a scaleup
+ action. When a VM is deployed from a template, the VM can start taking the traffic from the
+ load balancer without any admin intervention. For example, if the VM is deployed for a Web
+ service, it should have the Web server running, the database connected, and so on.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Compute offering</emphasis>: A predefined set of virtual hardware
+ attributes, including CPU speed, number of CPUs, and RAM size, that the user can select when
+ creating a new virtual machine instance. Choose one of the compute offerings to be used
+ while provisioning a VM instance as part of scaleup action.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Min Instance</emphasis>: The minimum number of active VM instances
+ that is assigned to a load balancing rule. The active VM instances are the application
+ instances that are up and serving the traffic, and are being load balanced. This parameter
+ ensures that a load balancing rule has at least the configured number of active VM instances
+ are available to serve the traffic.</para>
+ <note>
+ <para>If an application, such as SAP, running on a VM instance is down for some reason, the
+ VM is then not counted as part of Min Instance parameter, and the AutoScale feature
+ initiates a scaleup action if the number of active VM instances is below the configured
+ value. Similarly, when an application instance comes up from its earlier down state, this
+ application instance is counted as part of the active instance count and the AutoScale
+ process initiates a scaledown action when the active instance count breaches the Max
+ instance value.</para>
+ </note>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Max Instance</emphasis>: Maximum number of active VM instances
+ that <emphasis role="bold">should be assigned to </emphasis>a load balancing rule. This
+ parameter defines the upper limit of active VM instances that can be assigned to a load
+ balancing rule.</para>
+ <para>Specifying a large value for the maximum instance parameter might result in provisioning
+ large number of VM instances, which in turn leads to a single load balancing rule exhausting
+ the VM instances limit specified at the account or domain level.</para>
+ <note>
+ <para>If an application, such as SAP, running on a VM instance is down for some reason, the
+ VM is not counted as part of Max Instance parameter. So there may be scenarios where the
+ number of VMs provisioned for a scaleup action might be more than the configured Max
+ Instance value. Once the application instances in the VMs are up from an earlier down
+ state, the AutoScale feature starts aligning to the configured Max Instance value.</para>
+ </note>
+ </listitem>
+ </itemizedlist>
+ <para>Specify the following scale-up and scale-down policies:</para>
+ <itemizedlist>
+ <listitem>
+ <para><emphasis role="bold">Duration</emphasis>: The duration, in seconds, for which the
+ conditions you specify must be true to trigger a scaleup action. The conditions defined
+ should hold true for the entire duration you specify for an AutoScale action to be invoked.
+ </para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Counter</emphasis>: The performance counters expose the state of
+ the monitored instances. By default, &PRODUCT; offers four performance counters: Three SNMP
+ counters and one NetScaler counter. The SNMP counters are Linux User CPU, Linux System CPU,
+ and Linux CPU Idle. The NetScaler counter is ResponseTime. The root administrator can add
+ additional counters into &PRODUCT; by using the &PRODUCT; API. </para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Operator</emphasis>: The following five relational operators are
+ supported in AutoScale feature: Greater than, Less than, Less than or equal to, Greater than
+ or equal to, and Equal to.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Threshold</emphasis>: Threshold value to be used for the counter.
+ Once the counter defined above breaches the threshold value, the AutoScale feature initiates
+ a scaleup or scaledown action.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Add</emphasis>: Click Add to add the condition.</para>
+ </listitem>
+ </itemizedlist>
+ <para>Additionally, if you want to configure the advanced settings, click Show advanced settings,
+ and specify the following:</para>
+ <itemizedlist>
+ <listitem>
+ <para><emphasis role="bold">Polling interval</emphasis>: Frequency in which the conditions,
+ combination of counter, operator and threshold, are to be evaluated before taking a scale up
+ or down action. The default polling interval is 30 seconds.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Quiet Time</emphasis>: This is the cool down period after an
+ AutoScale action is initiated. The time includes the time taken to complete provisioning a
+ VM instance from its template and the time taken by an application to be ready to serve
+ traffic. This quiet time allows the fleet to come up to a stable state before any action can
+ take place. The default is 300 seconds.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Destroy VM Grace Period</emphasis>: The duration in seconds, after
+ a scaledown action is initiated, to wait before the VM is destroyed as part of scaledown
+ action. This is to ensure graceful close of any pending sessions or transactions being
+ served by the VM marked for destroy. The default is 120 seconds.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Security Groups</emphasis>: Security groups provide a way to
+ isolate traffic to the VM instances. A security group is a group of VMs that filter their
+ incoming and outgoing traffic according to a set of rules, called ingress and egress rules.
+ These rules filter network traffic according to the IP address that is attempting to
+ communicate with the VM.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Disk Offerings</emphasis>: A predefined set of disk size for
+ primary data storage. </para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">SNMP Community</emphasis>: The SNMP community string to be used by
+ the NetScaler device to query the configured counter value from the provisioned VM
+ instances. Default is public.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">SNMP Port</emphasis>: The port number on which the SNMP agent that
+ run on the provisioned VMs is listening. Default port is 161. </para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">User</emphasis>: This is the user that the NetScaler device use to
+ invoke scaleup and scaledown API calls to the cloud. If no option is specified, the user who
+ configures AutoScaling is applied. Specify another user name to override.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis role="bold">Apply</emphasis>: Click Apply to create the AutoScale
+ configuration.</para>
+ </listitem>
+ </itemizedlist>
+ <formalpara>
+ <title>Disabling and Enabling an AutoScale Configuration</title>
+ <para>If you want to perform any maintenance operation on the AutoScale VM instances, disable
+ the AutoScale configuration. When the AutoScale configuration is disabled, no scaleup or
+ scaledown action is performed. You can use this downtime for the maintenance activities. To
+ disable the AutoScale configuration, click the Disable AutoScale<inlinemediaobject>
+ <imageobject>
+ <imagedata fileref="./images/enable-disable-autoscale.png"/>
+ </imageobject>
+ <textobject>
+ <phrase>EnableDisable.png: button to enable or disable AutoScale.</phrase>
+ </textobject>
+ </inlinemediaobject>button.</para>
+ </formalpara>
+ <para>The button toggles between enable and disable, depending on whether AutoScale is currently
+ enabled or not. After the maintenance operations are done, you can enable the AutoScale
+ configuration back. To enable, open the AutoScale configuration page again, then click the
+ Enable AutoScale<inlinemediaobject>
+ <imageobject>
+ <imagedata fileref="./images/enable-disable-autoscale.png"/>
+ </imageobject>
+ <textobject>
+ <phrase>EnableDisable.png: button to enable or disable AutoScale.</phrase>
+ </textobject>
+ </inlinemediaobject>button.</para>
+ <formalpara id="update-autoscale">
+ <title>Updating an AutoScale Configuration</title>
+ <para>You can update the various parameters and add or delete the conditions in a scaleup or
+ scaledown rule. Before you update an AutoScale configuration, ensure that you disable the
+ AutoScale load balancer rule by clicking the Disable AutoScale button.</para>
+ </formalpara>
+ <para>After you modify the required AutoScale parameters, click Apply. To apply the new AutoScale
+ policies, open the AutoScale configuration page again, then click the Enable AutoScale
+ button.</para>
+ <formalpara>
+ <title>Runtime Considerations</title>
+ <para/>
+ </formalpara>
+ <itemizedlist>
+ <listitem>
+ <para>An administrator should not assign a VM to a load balancing rule which is configured for
+ AutoScale.</para>
+ </listitem>
+ <listitem>
+ <para>Before a VM provisioning is completed if NetScaler is shutdown or restarted, the
+ provisioned VM cannot be a part of the load balancing rule though the intent was to assign
+ it to a load balancing rule. To workaround, rename the AutoScale provisioned VMs based on
+ the rule name or ID so at any point of time the VMs can be reconciled to its load balancing
+ rule.</para>
+ </listitem>
+ <listitem>
+ <para>Making API calls outside the context of AutoScale, such as destroyVM, on an autoscaled
+ VM leaves the load balancing configuration in an inconsistent state. Though VM is destroyed
+ from the load balancer rule, NetScaler continues to show the VM as a service assigned to a
+ rule.</para>
+ </listitem>
+ </itemizedlist>
+</section>
http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/499c474e/docs/en-US/configure-snmp-rhel.xml
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diff --git a/docs/en-US/configure-snmp-rhel.xml b/docs/en-US/configure-snmp-rhel.xml
new file mode 100644
index 0000000..bd227ff
--- /dev/null
+++ b/docs/en-US/configure-snmp-rhel.xml
@@ -0,0 +1,86 @@
+<?xml version='1.0' encoding='utf-8' ?>
+<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
+%BOOK_ENTITIES;
+]>
+<!-- Licensed to the Apache Software Foundation (ASF) under one
+ or more contributor license agreements. See the NOTICE file
+ distributed with this work for additional information
+ regarding copyright ownership. The ASF licenses this file
+ to you under the Apache License, Version 2.0 (the
+ "License"); you may not use this file except in compliance
+ with the License. You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing,
+ software distributed under the License is distributed on an
+ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ KIND, either express or implied. See the License for the
+ specific language governing permissions and limitations
+ under the License.
+-->
+<section id="configure-snmp-rhel">
+ <title>Configuring SNMP Community String on a RHEL Server</title>
+ <para>The SNMP Community string is similar to a user id or password that provides access to a
+ network device, such as router. This string is sent along with all SNMP requests. If the
+ community string is correct, the device responds with the requested information. If the
+ community string is incorrect, the device discards the request and does not respond.</para>
+ <para>The NetScaler device uses SNMP to communicate with the VMs. You must install SNMP and
+ configure SNMP Community string for a secure communication between the NetScaler device and the
+ RHEL machine.</para>
+ <orderedlist>
+ <listitem>
+ <para>Ensure that you installed SNMP on RedHat. If not, run the following command:</para>
+ <screen>yum install net-snmp-utils</screen>
+ </listitem>
+ <listitem>
+ <para>Edit the /etc/snmp/snmpd.conf file to allow the SNMP polling from the NetScaler
+ device.</para>
+ <orderedlist>
+ <listitem>
+ <para>Map the community name into a security name (local and mynetwork, depending on where
+ the request is coming from):</para>
+ <note>
+ <para>Use a strong password instead of public when you edit the following table.</para>
+ </note>
+ <screen># sec.name source community
+com2sec local localhost public
+com2sec mynetwork 0.0.0.0 public</screen>
+ <note>
+ <para>Setting to 0.0.0.0 allows all IPs to poll the NetScaler server.</para>
+ </note>
+ </listitem>
+ <listitem>
+ <para>Map the security names into group names: </para>
+ <screen># group.name sec.model sec.name
+group MyRWGroup v1 local
+group MyRWGroup v2c local
+group MyROGroup v1 mynetwork
+group MyROGroup v2c mynetwork</screen>
+ </listitem>
+ <listitem>
+ <para>Create a view to allow the groups to have the permission to:</para>
+ <screen>incl/excl subtree mask view all included .1 </screen>
+ </listitem>
+ <listitem>
+ <para>Grant access with different write permissions to the two groups to the view you
+ created.</para>
+ <screen># context sec.model sec.level prefix read write notif
+ access MyROGroup "" any noauth exact all none none
+ access MyRWGroup "" any noauth exact all all all </screen>
+ </listitem>
+ </orderedlist>
+ </listitem>
+ <listitem>
+ <para>Unblock SNMP in iptables.</para>
+ <screen>iptables -A INPUT -p udp --dport 161 -j ACCEPT</screen>
+ </listitem>
+ <listitem>
+ <para>Start the SNMP service:</para>
+ <screen>service snmpd start</screen>
+ </listitem>
+ <listitem>
+ <para>Ensure that the SNMP service is started automatically during the system startup:</para>
+ <screen>chkconfig snmpd on</screen>
+ </listitem>
+ </orderedlist>
+</section>
http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/499c474e/docs/en-US/external-firewalls-and-load-balancers.xml
----------------------------------------------------------------------
diff --git a/docs/en-US/external-firewalls-and-load-balancers.xml b/docs/en-US/external-firewalls-and-load-balancers.xml
index 1452804..6ca49f0 100644
--- a/docs/en-US/external-firewalls-and-load-balancers.xml
+++ b/docs/en-US/external-firewalls-and-load-balancers.xml
@@ -3,26 +3,31 @@
<!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
%BOOK_ENTITIES;
]>
-
<!-- Licensed to the Apache Software Foundation (ASF) under one
- or more contributor license agreements. See the NOTICE file
- distributed with this work for additional information
- regarding copyright ownership. The ASF licenses this file
- to you under the Apache License, Version 2.0 (the
- "License"); you may not use this file except in compliance
- with the License. You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing,
- software distributed under the License is distributed on an
- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- KIND, either express or implied. See the License for the
- specific language governing permissions and limitations
- under the License.
+ or more contributor license agreements. See the NOTICE file
+ distributed with this work for additional information
+ regarding copyright ownership. The ASF licenses this file
+ to you under the Apache License, Version 2.0 (the
+ "License"); you may not use this file except in compliance
+ with the License. You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing,
+ software distributed under the License is distributed on an
+ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ KIND, either express or implied. See the License for the
+ specific language governing permissions and limitations
+ under the License.
-->
-
<section id="external-firewalls-and-load-balancers">
- <title>External Firewalls and Load Balancers</title>
- <para>&PRODUCT; is capable of replacing its Virtual Router with an external Juniper SRX device and an optional external NetScaler or F5 load balancer for gateway and load balancing services. In this case, the VMs use the SRX as their gateway.</para>
+ <title>External Firewalls and Load Balancers</title>
+ <para>&PRODUCT; is capable of replacing its Virtual Router with an external Juniper SRX device and
+ an optional external NetScaler or F5 load balancer for gateway and load balancing services. In
+ this case, the VMs use the SRX as their gateway.</para>
+ <xi:include href="using-netscaler-load-balancers.xml" xmlns:xi="http://www.w3.org/2001/XInclude"/>
+ <xi:include href="configure-snmp-rhel.xml" xmlns:xi="http://www.w3.org/2001/XInclude"/>
+ <xi:include href="initial-setup-of-external-firewalls-loadbalancers.xml"
+ xmlns:xi="http://www.w3.org/2001/XInclude"/>
+ <xi:include href="ongoing-configuration-of-external-firewalls-loadbalancer.xml"
+ xmlns:xi="http://www.w3.org/2001/XInclude"/>
+ <xi:include href="autoscale.xml" xmlns:xi="http://www.w3.org/2001/XInclude"/>
</section>
http://git-wip-us.apache.org/repos/asf/incubator-cloudstack/blob/499c474e/docs/en-US/ongoing-configuration-of-external-firewalls-loadbalancer.xml
----------------------------------------------------------------------
diff --git a/docs/en-US/ongoing-configuration-of-external-firewalls-loadbalancer.xml b/docs/en-US/ongoing-configuration-of-external-firewalls-loadbalancer.xml
new file mode 100644
index 0000000..c90c7ad
--- /dev/null
+++ b/docs/en-US/ongoing-configuration-of-external-firewalls-loadbalancer.xml
@@ -0,0 +1,46 @@
+<?xml version='1.0' encoding='utf-8' ?>
+<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
+<!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
+%BOOK_ENTITIES;
+]>
+<!-- Licensed to the Apache Software Foundation (ASF) under one
+ or more contributor license agreements. See the NOTICE file
+ distributed with this work for additional information
+ regarding copyright ownership. The ASF licenses this file
+ to you under the Apache License, Version 2.0 (the
+ "License"); you may not use this file except in compliance
+ with the License. You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing,
+ software distributed under the License is distributed on an
+ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ KIND, either express or implied. See the License for the
+ specific language governing permissions and limitations
+ under the License.
+-->
+<section id="ongoing-configuration-of-external-firewalls-loadbalancer">
+ <title>Ongoing Configuration of External Firewalls and Load Balancers</title>
+ <para>Additional user actions (e.g. setting a port forward) will cause further programming of the
+ firewall and load balancer. A user may request additional public IP addresses and forward
+ traffic received at these IPs to specific VMs. This is accomplished by enabling static NAT for a
+ public IP address, assigning the IP to a VM, and specifying a set of protocols and port ranges
+ to open. When a static NAT rule is created, &PRODUCT; programs the zone's external firewall with
+ the following objects:</para>
+ <itemizedlist>
+ <listitem>
+ <para>A static NAT rule that maps the public IP address to the private IP address of a
+ VM.</para>
+ </listitem>
+ <listitem>
+ <para>A security policy that allows traffic within the set of protocols and port ranges that
+ are specified.</para>
+ </listitem>
+ <listitem>
+ <para>A firewall filter counter that measures the number of bytes of incoming traffic to the
+ public IP.</para>
+ </listitem>
+ </itemizedlist>
+ <para>The number of incoming and outgoing bytes through source NAT, static NAT, and load balancing
+ rules is measured and saved on each external element. This data is collected on a regular basis
+ and stored in the &PRODUCT; database.</para>
+</section>