Cisco Virtual Security Gateway for Nexus 1000V Series Switch Release Notes, Release 4.2(1)VSG1(4.1)

Cisco Virtual Security Gateway for Cisco Nexus 1000V Series Switch Release Notes, Release 4.2(1)VSG1(4.1)

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Release Date: August 21, 2012

Part Number: OL-27570-01
Current Release: Cisco VSG Release 4.2(1)VSG1(4.1)

This document describes the features, limitations, and caveats for the Cisco Virtual Security Gateway and Cisco Virtual Network Management Center software. Use this document in combination with documents listed in the “Related Documentation” section. The following is the change history for this document.

Contents

This document includes the following sections:

• Introduction
• Software Compatibility
• Features
• New and Changed Information
• Limitations and Restrictions
• VSG Scalability Matrix
• Open Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)
• Resolved Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)
• Related Documentation
• Obtaining Documentation and Submitting a Service Request

Introduction

The Cisco Virtual Security Gateway (VSG) for the Cisco Nexus 1000V Series switch is a virtual firewall appliance that provides trusted access to virtual data center and cloud environments with dynamic policy-driven operation, mobility-transparent enforcement, and scale-out deployment for dense multitenancy. The Cisco VSG enables a broad set of multitenant workloads that have varied security profiles to share a common compute infrastructure. By associating one or more Virtual Machines into distinct trust zones, the Cisco VSG ensures that access to trust zones is controlled and monitored through established security policies.

Together, the Cisco VSG and Cisco Nexus 1000V Virtual Ethernet Module provide the following benefits:

• Efficient deployment—Each Cisco VSG can protect Virtual Machines across multiple physical servers, which eliminates the need to deploy one virtual appliance per physical server.
• Performance optimization—By offloading Fast-Path to one or more Cisco Nexus 1000V VEM vPath modules, the Cisco VSG boosts its performance through distributed vPath-based enforcement.
• Operational simplicity—You can insert a Cisco VSG in one-arm mode without creating multiple switches or temporarily migrating VMs to different switches or servers. Zone scaling is based on security profile, not on vNICs that are limited for virtual appliances.
• High availability—For each tenant, you can deploy a Cisco VSG in an active-standby mode to ensure a highly available operating environment with vPath redirecting packets to the standby Cisco VSG when the primary Cisco VSG is unavailable
• Independent capacity planning—You can place a Cisco VSG on a dedicated server, controlled by the security operations team so that maximum compute capacity can be allocated to application workloads. Capacity planning can occur independently across server and security teams, and operational segregation across security, network, and server teams can be maintained.

Software Compatibility

The servers that run the Cisco Nexus 1000V VSM and VEM must be in the VMware Hardware Compatibility list, which is a requirement for running the ESX 4.1 or 5.0 software.

For additional compatibility information, see the Cisco Nexus 1000V Compatibility Information, Release 4.2(1)SV1(5.2).

Features

This section provides the following information about this release:

• Product Architecture
• Trusted Multitenant Access
• Dynamic (Virtualization-Aware) Operation
• Setting Up Cisco VSG and VLAN Usages

Trusted Multitenant Access

You can transparently insert a Cisco VSG into the VMware vSphere environment where the Cisco Nexus 1000V distributed virtual switch is deployed. Upon insertion, one or more instances of the Cisco VSG is deployed on a per-tenant basis, which allows a highly scaled-out deployment across many tenants. Because tenants are isolated from each other, no traffic can cross tenant boundaries. Depending on the use case, you can deploy Cisco VSG at the tenant level, at the virtual data center (vDC) level, or at the vApp level.

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Note The Cisco VSG is not inherently multitenant. It must be explicit within each tenant.

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As VMs are instantiated for a given tenant, association to security profiles and zone membership occurs immediately through binding with the Cisco Nexus 1000V port profile. Upon instantation, each VM is placed into a logical trust zone. Security profiles contain context-aware rule sets that specify access policies for traffic that enters and exits each zone. With the VM and network contexts, you can leverage custom attributes to define zones directly through security profiles. The profiles are applied to zone-to-zone traffic and external-to-zone/zone-to-external traffic. This enforcement occurs within a VLAN because a VLAN often identifies a tenant boundary.

The Cisco VSGs evaluate access control rules and then offloads enforcement to the Cisco Nexus 1000V VEM vPath module for performance optimization. Access is permitted or denied based on policies. The Cisco VSG provides policy-based traffic monitoring capability and generates access logs.

New and Changed Information

This section describes the new and changed features for the Cisco Virtual Security Gateway for Nexus 1000V Series Switch, Release 4.2(1)VSG1(4.1).

Cisco vPath Service Chaining

Service chaining allows multiple service nodes to be included in a service path so that the packets that belong to a particular flow can pass through this service chain. Each service node in a chain uses the security profile specified in the vservice command for that node.

Cisco VSG Release 4.2(1)VSG1(4.1) supports service chaining that allows the packets on a flow to be directed to more than one service node. Cisco vPath service chaining allows two types of service nodes:

• Cisco VSG
• ASA 1000V

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Note You can configure the vPath traffic to bypass the Cisco VSG nodes in a service chain, to improve the network latency. This for only traffic traversing between the inside and outside networks, wherein only the Cisco ASA processes the traffic. This feature is supported for Cisco Nexus 1000V, Release 4.2(1)SV2(1.1) onwards.

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Selective TCP State Checks

Cisco VSG Release 4.2(1)VSG1(4.1) supports the selective TCP state checks that can be configured to set the invalid-ack, seq-past-window, and window-variation parameters for the data packets.

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Note This feature is supported for Cisco Nexus 1000V, Release 4.2(1)SV2(1.1) onwards.

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Limitations and Restrictions

The Cisco Virtual Security Gateway for Nexus 1000V Series switch has the following limitations and restrictions:

• Jumbo frames cannot be configured for the Cisco VSG management interface.
• Vmotion of the Cisco VSG is validated for host upgrades only and not for DRS purposes.
• Enabling firewall protection on a router virtual machine may cause problems for policies based on VM attributes; firewall protection should be enabled only for end-point Virtual Machines.
• OVA Installation Behavior

During OVA installation, the following error message might be seen:

The network card VirtualE1000 has dvPort backing, which is not supported. This could be because the host does not support vDS, or because the host is not using vDS.

Workaround: Ensure that all three network interfaces in the Cisco VSG port profile are set to VM Network (port profile from vSwitch) during OVA installation. Once the virtual machine is created, the port profile for these three interfaces should be changed according to the Cisco Virtual Security Gateway, Release 4.2(1)VSG1(2) and Cisco Virtual Network Management Center, Release 1.2 Installation and Upgrade Guide.

• If the VSM is down when the Cisco VSG is powered on, the Cisco VSG continuously tries to reboot.

Workaround: To prevent this situation, configure the Service VLAN and the HA VLAN used by the Cisco VSG as system vlan vlan_number in the uplink port profile.

• Layer 2 Mode

When the VEM communicates with the Cisco VSG in the Layer 2 mode, an additional header with 74 bytes is added to the original packet. The VEM fragments the packet if it exceeds the uplink MTU.

For better performance, increase the MTU of all links between the VEM and the Cisco VSG by 74 bytes to account for packet encapsulation which occurs for communication between vPath and the Cisco VSG. For example, if the MTU values of the client and server VMs and uplink are all 1500 bytes, set the uplink MTU to 1574 bytes.

• Layer 3 Mode

– When the VEM communicates with the Cisco VSG in the Layer 3 mode, an additional header with 94 bytes is added to the original packet. The VEM does not support fragmentation in Layer 3 mode and the ports/network-elements (which carry vPath encapsulated packets) must be configured in such a way that the vPath overhead is accommodated. For example, if MTU values of client and server VMs and uplink are all 1500 bytes, set the uplink MTU to 1594 bytes.

– If the jumbo frames are enabled in the network, make sure the MTU of the client and server VMs are 94 bytes smaller than the uplink. For example, if the uplink MTU is 9000 bytes, set the MTU of the client and server VMs to 8906 bytes.

– When encapsulated traffic that is destined to a Cisco VSG is connected to a different subnet other than the vmknic subnet, the VEM does not use the VMware host routing table. Instead, the vmknic initiates an ARP for the remote Cisco VSG IP addresses. You must configure the upstream router to respond by using the proxy ARP feature.

– The VEM does not support a routing functionality and it is assumed that the upstream switch/router is configured with the proxy-ARP configuration.

• Configuring a Rule with a Reset Action

Configuring a rule with a reset action for the non-TCP/UDP protocol will result in dropped traffic. However, the syslog generated for this traffic shows that the action performed for the traffic is reset as shown below:

• Cisco VSG CLI Session Timeout

The CLI session for the Cisco VSG version 1.3x that is newly deployed will time out after a period of five minutes of an inactivity. The CLI session time out does not work on Cisco VSG that has been upgraded from version 1.0x.

• On the Cisco VSG that is upgraded from version 1.0x, the show running-config will consist only of the following items:

- gold001-vsg01# sh run | i line|timeout

- line console

- gold001-vsg01#

As a workaround, when upgrade is done from 1.0x to 1.3 version of Cisco VSG, “exec-timeout 5” can be configured under “line console” and “line vty” command modes to enable a five minutes CLI session inactivity timeout.

• VM Name Display Length Limitation

VM names for VMs on ESX 4.1 hosts that exceed 21 characters are not displayed properly on the VSM. When you use a show vservice command that displays the port profile name, for example, the show vservice port brief port-profile port-profile-name command, only VMs with names that are 21 characters or less are displayed correctly. Longer VM names may cause the VM name to be truncated, or extra characters to be appended to the VM name. Depending on the network adapter, the name length limitation may vary. For example:

– The E1000 or VMXNET 2 network adapters allow 26-character names. At 27 characters, the word ‘.eth’ is appended to the VM name. With each addition to the VM name, a character is truncated from the word ‘.eth’. After 31 characters, the VM name is truncated.

– The VMXNET 3 network adapters allow 21-character names. At 22 characters, the word ‘ethernet’ is appended to the VM name. With each addition to the VM name, a character is truncated from the word ‘ ethernet’. After 30 characters, the VM name is truncated.

Workaround: This is a display issue with ESX Release 4.1 only. Use VM names of 21 characters or less to avoid this issue.

VSG Scalability Matrix

The following table presents a feature-based comparative analysis between two VSGs having different number of virtual CPUs and VNMC:

Caveats

This section include the following topics:

• Open Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)
• Open Caveats—Cisco VSG Release 4.2(1)VSG1(3.1)
• Resolved Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)

Open Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)

The following are descriptions of the caveats in Cisco Virtual Security Gateway for Nexus 1000V Series switch, Release 4.2(1)VSG1(4.1). The ID links open the Cisco Bug Toolkit.

Open Caveats—Cisco VSG Release 4.2(1)VSG1(3.1)

The following are descriptions of the caveats in Cisco Virtual Security Gateway for Nexus 1000V Series switch, Release 4.2(1)VSG1(3.1). The ID links open the Cisco Bug Toolkit.

Resolved Caveats—Cisco VSG Release 4.2(1)VSG1(4.1)

The following table describes the resolved caveats in Cisco Virtual Security Gateway for Nexus 1000V Series switch, Release 4.2(1)VSG1(4.1). The ID links open the Cisco Bug Toolkit.

Related Documentation

This section contains information about the documentation available for Cisco Virtual Security Gateway and related products.

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service request, and gathering additional information, see What’s New in Cisco Product Documentation.

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