In this section:
This section provides an overview of creating a VM on a KVM Host along with descriptions of reference configurations and detailed procedures.
The example files in this section were obtained from the KVM Installer (host-network-files).
Configuration Overview
A DSC SWe deployment consists of a single or multiple VMs installed on a KVM Host. The DSC software contains a Linux-based operating system and an application layer that provides both Diameter and SS7 routing functions. To enable the DSC SWe, the VM requires external network connections to activate the core routing function on the DSC SWe. The Installer tool establishes the required network connections from the VM to the KVM Host.
Note
The KVM Host is the physical server hardware that runs the host OS, on which the KVM hypervisor software is installed. The core DSC Linux OS installed on a VM runs the guest OS.
Three levels of network interfaces are defined to establish connections from the VM to the physical ports on the KVM Host, as follows:
- Software level contains the virtual machine (VM) network tap interfaces
- KVM Host operating system (OS) level contains the virtual Bridge interfaces
- KVM Host hardware level consists of external (physical) Ethernet interfaces
At the software level, the DSC SWe requires virtual connections to the VM network tap interfaces to enable the core routing function. The KVM Host OS level consists of connections made between the VM's network tap interfaces and the KVM Host's virtual Bridge devices. The KVM Host hardware level consists of connections made between the virtual Bridges and external Ethernet ports.
The external network consists of the following components:
- Physical cable connections between the KVM Host and the next hop router
- Direct cable connections between physical KVM Hosts to enable the VM-to-VM High Availability (HA) communication link
Tip
Considering the external network infrastructure before defining the first three network levels (software, KVM Host OS, and hardware) simplifies the KVM host configuration once the required external network connections are known.
Network tap interfaces are created within each VM, and are defined as mgt0, mgt1, ha0, pkt0, pkt1, pkt2, pkt3, imf0, and imf1.
The following figure shows each VM network tap interface connected to the corresponding virtual Bridge on a KVM Host.
VM Network Taps To Virtual Bridge Connections
Management interfaces (mgt0 and mgt1) are configured on Routing and Management VM1 and VM2 and carry data traffic for management functions (for example, user login). The packet interfaces (pkt[0-3]) are each assigned a local IP address and are designated for Diameter or SS7 network traffic. The virtual ha0 network interface is used to communicate provisioning and status data between VMs. The monitoring interfaces (imf0 and imf1) are for traffic monitoring.
The High Availability (HA) interface is a dedicated low-latency communication interface designed to improve communication robustness between VMs and used to communicate status and other network data. The HA interface is implemented in the active-active configuration using two VMs operating independently on either a single KVM Host or two individual KVM Hosts. The active-active architecture is resilient to system failures by providing an auto mechanism that allows one DSC SWe to take control and provide service if the other fails.
The Installer tool provides network configuration scripts based on KVM Host reference configurations. The network configuration scripts define the virtual Bridge devices on the KVM Host and establish connections between the virtual Bridges and external Ethernet ports.
Note
The Installer tool supports Linux KVM Host hardware platforms consisting of four or eight external Ethernet ports, depending on the COTS platform selected for the DSC SWe installation.
Three general categories of KVM Host reference configurations are supported, as follows:
- 8-port KVM Host Reference Configurations
- 4-port KVM Host Reference Configurations
- Custom KVM Host Configurations (user defined)
A number of possible external network scenarios may be implemented when considering all levels of KVM Host network connectivity. The following table provides a summary of some of the recommended configurations.
KVM Host Reference Configurations
| Reference Configuration | KVM Host Configuration | Physical Hosts | HA Model | VMs | Ethernet Ports | Comments |
|---|---|---|---|---|---|---|
| RC1 |
| 2 | Bonded ha0 | 1 per KVM Host | 8 per KVM Host | Baseline reference configuration (most common). |
RC2 |
| 2 | Bonded ha0 | 2 (or more) per KVM Host | 8 per KVM Host | Network model is identical to RC1. |
RC3 |
| 2 | Simple ha0 (no bonding) | 1 per KVM Host | 4 per KVM Host | Option is available for reducing the number of server ports. |
The following table describes the external (physical) port mapping for each reference configuration shown in the preceding table.
Reference Configurations – Bridge To Physical Port Mapping
| Bridge | Reference Configuration (external ports) | ||
|---|---|---|---|
| RC1 | RC2 | RC3 | |
mgt0 | eth0 | eth0 | eth0 (KVM Host #1) |
| mgt1 | eth4 | eth4 | eth0 (KVM Host #2) |
| ha0 | bond1 (eth1 + eth5) | bond1 (eth1 + eth5) | eth1 |
| pkt0 | eth2 | eth2 | eth2 |
| pkt1 | eth3 | eth3 | eth3 |
| pkt2 | eth6 | eth6 | - |
| pkt3 | eth7 | eth7 | - |
| imf0 | eth6.10 | eth6.10 | eth2.10 |
| imf1 | eth7.11 | eth7.11 | eth3.11 |
Note
The 4-port KVM Host reference configuration, RC3, requires unique ethernet port assignments. The individual KVM Hosts cannot have the same physical ethernet ports assigned to bridge devices mgt0 or mgt1. For example, if eth0 is defined for mgt0 on one KVM Host, the other host must have eth0 defined on mgt1.
8-Port KVM Host Reference Configurations (RC1 and RC2)
The following two 8-port KVM Host configurations are recommended:
- Two VMs installed on separate 8-port physical KVM Hosts (baseline reference configuration).
- Two VMs installed on a single 8-port physical KVM Host.
The baseline reference configuration consists of two VMs installed on separate physical KVM Hosts, each with eight external Ethernet ports. The virtual Bridge to physical port connections are influenced by the network resources available on the chosen COTS platform. For example, a 4-port COTS sever with a 4-port NIC installed has a total of eight external Ethernet ports. For system redundancy, a bonded HA link using dedicated ports is recommended for low-latency VM-to-VM communication between servers.
The following figure shows an example of the baseline reference configuration.
Two VMs Installed On Separate 8-Port KVM Hosts
Note
The preceding figure shows two external ports bonded together ('eth1' and 'eth5') to form a low latency, fault tolerant HA communication link between VMs. To connect the HA interfaces on each KVM Host, a direct cable (bundle) connection is recommended. For additional system reliability, it is recommended to bond those ports on the host that are physically located on separate NICs. For example, port 'eth1' residing on NIC_1 is bonded with port 'eth5' on NIC_2.
The following figure shows a reference configuration consisting of two VMs installed on one physical 8-port KVM Host.
Two VMs Installed On A KVM Host With Eight Physical Ethernet Ports
Note
The preceding figure shows an example of the single-server deployment model and is not supported. The single server deployment model consists of multiple VMs installed on a single KVM Host, which is not fault tolerant. The recommended configuration is the multi-server deployment model consisting of multiple VMs installed across multiple KVM Hosts for system redundancy and network resilience.
4-Port KVM Host Reference Configurations (RC3)
The following figure shows a reference configuration consisting of two VMs installed on physically separate 4-port KVM Hosts.
Two VMs Installed On Separate 4-port KVM Hosts
Note
The 4-port KVM Host reference configuration, RC3, requires unique ethernet port assignments. The individual KVM Hosts cannot have the same physical ethernet ports assigned to bridge devices mgt0 or mgt1. For example, if eth0 is defined for mgt0 on one KVM Host, the other host must have eth0 defined on mgt1.
The following figure shows a 4-port KVM Host reference configuration with VLAN trunking enabled on both KVM Hosts.
Two VMs Installed On Separate KVM Hosts, Each With Four Physical Ports And VLAN Trunking Enabled
VLAN trunks are recommended for KVM Hosts with less than eight external Ethernet ports. For example, a common COTS platform with low port density has four Gigabit (or 2 x 10 GbE) Ethernet ports available for external networks. Multiple IP addresses are stacked on one or more external ports to avoid segregating the subnets using VLANs.
Custom KVM Host Configurations
You can elect to perform a custom KVM Host configuration for the DSC SWe installation. External port density and the Linux OS virtual Bridge configuration are dependent on the chosen COTS platform, which determines the external port mapping. Virtual Bridge names and external Ethernet port labels are defined by the KVM Host Linux OS. The DSC SWe requires a standard set of Linux virtual Bridges configured on a KVM Host. The internal connections from the virtual Bridge devices to the external Ethernet ports are customized (that is, user-defined) to enable VM communication with the external network.
The following figure shows the required port mapping between virtual Bridges and physical ports to enable external communication.
8-port KVM Host With User-Defined Physical Ethernet Ports
Note
The external Ethernet port labels (or port names) on a chosen COTS platform are user-defined and may not resemble the physical port labels on the server hardware. For example, common external port labels are: Port 1, Port 2, Port 3, and Port 4. The number of external ports is determined by the selected COTS platform.
Tip
A robust network design offers flexibility and network capacity for the core routing function on the DSC SWe.
The following figure shows an example 4-port KVM Host custom configuration.
4-port KVM Host Configuration Example
Note
The preceding figure shows a configuration example with external ports labeled 'em1' through 'em4', which is the default Linux RedHat OS external port configuration. The example shows a VLAN trunk defined on virtual ports 'em3.10' and 'em4.11', to segregate traffic from the connections to virtual Bridges 'imf0' and 'imf1'. The Bridges 'mgt1', 'pkt2', and 'pkt3' are not connected to any external ports, and hence, are considered inactive by the VM.
The following figure shows an example 4-port KVM Host configuration expanded to eight (4+4) external Ethernet ports using a 4-port Ethernet expansion card (NIC).
8-port KVM Host Configuration Example
Note
The preceding figure shows a configuration example with external ports, eth1 and eth5, bonded together to form the HA interface. A VLAN is created using external ports eth6.10 and eth7.11.
Configure the KVM Host
The Installer tool provides executable network configuration scripts to configure the KVM Host's virtual Bridge devices and physical Ethernet ports. The DSC Platform installation tar file contains a suite of network configuration scripts that are copied from the 'network-reference' folder in the DSC installation directory to the KVM Host OS Linux Red Hat directory /etc/sysconfig/network-scripts. The network configuration scripts are modeled on the supported Reference Configurations (RC1 and RC2). The configuration scripts are executed on the host to configure the virtual Bridge devices and define the external port mapping between the Bridges and the external Ethernet ports.
Note
A KVM Host running Linux Red Hat OS requires the network configuration scripts to be installed in the /etc/sysconfig/network-scripts directory. Other Linux operating systems (for example, Fedora) require the configuration scripts to be installed in a different directory. Please consult your Linux Vendor's OS Manual for further details.
The DSC SWe Installer requires the host Management IP address specified in the bridge devices (mgt0 or mgt1), not the Ethernet device (eth0).
The network configuration scripts provided by the DSC SWe Installer require the host Management IP address specified in the following bridge configuration files: ifcfg-mgt0 or ifcfg-mgt1. If the host Management IP address is specified in the standard Linux Ethernet device, eth0, the address must be moved to the applicable bridge device for successful execution of the network configuration scripts. For example, Red Hat OS platforms specify the host Management IP address in the network configuration file, ifcfg-eth0, as default. Copy or move the host Management IP address from ifcfg-eth0 to either ifcfg-mgt0 or ifcfg-mgt1, depending on your deployment configuration.
4-Port Reference Configuration (RC3)
A modification to one network configuration file is required on deployment of the 4-port reference configuration, RC3, consisting of dual 4-port KVM Hosts. The network configuration file, ifcfg-eth0, is modified on only one KVM Host, the other remains unchanged. The contents of the ifcfg-eth0 file located in the /etc/sysconfig/network-scripts/ directory, is modified as follows:
change: BRIDGE="mgt0" to: BRIDGE="mgt1"
Note
The 4-port KVM Host reference configuration, RC3, requires unique Ethernet port assignments. The individual KVM Hosts cannot have the same physical Ethernet ports assigned to bridge devices mgt0 or mgt1. For example, if eth0 is defined for mgt0 on one KVM Host, the other host must have eth0 defined on mgt1.
8-Port Reference Configuration (RC1 and RC2)
The network configuration scripts define the virtual Bridge to physical Ethernet port connections and are based on the supported reference configurations. Reference Configurations (RC1 and RC2) are modeled on a KVM Host running Linux Red Hat OS with four or eight external Ethernet ports labeled eth(0-4) or eth(0-7), as defined by the Red Hat OS. The network configuration scripts are modified for VM deployments on other COTS platforms. A network configuration script is defined for each external Ethernet port using the name format: ifcfg-ethX, where "X" is the corresponding external port number. For deployments on COTS platforms that use different external port labels, the network configuration scripts associated with the external ports must be re-named using the correct port labels on the host.
For example, a VM deployed on a Dell server as the KVM Host platform has different external port labels compared to a KVM Host using an HP ProLiant DL380e Gen8 platform. The 8-port Dell server uses four external (integrated) Ethernet ports labelled "em1", "em2", "em3", and "em4", and an additional NIC providing four additional ports labelled "p5p1", "p5p2", "p5p3", and "p5p4". The 8-port network configuration files provided by the Installer are renamed as follows:
"ifcfg-em1" "ifcfg-em2" "ifcfg-em3" "ifcfg-em4" "ifcfg-p5p1" "ifcfg-p5p2" "ifcfg-p5p3" "ifcfg-p5p4"
In addition, the contents of each file must be updated using the external port labels on the COTS platform. For instance, the default DEVICE values must be modified from the "eth" port designation (based on the reference configuration), to the required "em" or "p5p" port designations.
Direct cable connections (that is, crossover cables) are recommended to link the HA interfaces on the individual KVM Hosts. Contact Customer Support if the intent is to link the HA interfaces with network equipment (for example, a layer 2 router) as this will require internal re-configuration.
Obtain the Host Networking Files
Start
- Log onto a KVM Host or a Linux workstation for which you want to obtain the host networking files.
Enter the following command at the Linux prompt.
./dsc_swe_<release>_nb<date>_KVM.sh host-network-files
Example# ./dsc_swe_18_0_0_nb20190317_KVM.sh host-network-files
DSC SWe KVM Host Interaction ---------------------------- Verify requisite files in the archive... Processing hosts ---------------- Extracted file /tmp/dsc_swe_host_extra.tgz redhat/ redhat/4_port_simple_ha/ redhat/8_port_bonded_ha/ dscvm_host_add_vlan.sh dscvm_host_del_vlan.sh redhat/4_port_simple_ha/ifcfg-eth3 redhat/4_port_simple_ha/ifcfg-mgt0 redhat/4_port_simple_ha/ifcfg-ha0 redhat/4_port_simple_ha/ifcfg-mgt1 redhat/4_port_simple_ha/ifcfg-pkt0 redhat/4_port_simple_ha/ifcfg-pkt1 redhat/4_port_simple_ha/ifcfg-pkt2 redhat/4_port_simple_ha/ifcfg-eth2.10 redhat/4_port_simple_ha/ifcfg-pkt3 redhat/4_port_simple_ha/ifcfg-vm redhat/4_port_simple_ha/ifcfg-eth3.11 redhat/4_port_simple_ha/ifcfg-imf0 redhat/4_port_simple_ha/ifcfg-imf1 redhat/4_port_simple_ha/readme.txt redhat/4_port_simple_ha/ifcfg-eth0 redhat/4_port_simple_ha/ifcfg-eth1 redhat/4_port_simple_ha/ifcfg-eth2 redhat/8_port_bonded_ha/ifcfg-bond1 redhat/8_port_bonded_ha/ifcfg-eth3 redhat/8_port_bonded_ha/ifcfg-eth4 redhat/8_port_bonded_ha/ifcfg-eth5 redhat/8_port_bonded_ha/ifcfg-eth6 redhat/8_port_bonded_ha/ifcfg-eth7 redhat/8_port_bonded_ha/ifcfg-mgt0 redhat/8_port_bonded_ha/ifcfg-ha0 redhat/8_port_bonded_ha/ifcfg-mgt1 redhat/8_port_bonded_ha/ifcfg-pkt0 redhat/8_port_bonded_ha/ifcfg-pkt1 redhat/8_port_bonded_ha/ifcfg-pkt2 redhat/8_port_bonded_ha/ifcfg-pkt3 redhat/8_port_bonded_ha/ifcfg-vm redhat/8_port_bonded_ha/ifcfg-eth6.10 redhat/8_port_bonded_ha/ifcfg-eth7.11 redhat/8_port_bonded_ha/ifcfg-imf0 redhat/8_port_bonded_ha/ifcfg-imf1 redhat/8_port_bonded_ha/readme.txt redhat/8_port_bonded_ha/ifcfg-eth0 redhat/8_port_bonded_ha/ifcfg-eth1 redhat/8_port_bonded_ha/ifcfg-eth2 Files extracted to /tmp/dsc_host_networking/ These example "sysconfig/network-scripts/ifcfg-*" scripts (Red Hat O/S) can be used after editing - need to add physical interface names and IP address values. These can be applied to the KVM hosts to setup bridges as described in the DSC documentation. There are also scripts to assist with host vlan addition and deletion.
Verify the Host Configuration
Start
Execute the command at the prompt:
# ifconfig
The configured virtual Bridge devices and the port mapping are displayed.
Execute the command at the prompt:
# brctl show
The virtual Bridge name and member interfaces for each Bridge are displayed.Examplebridge name bridge id STP enabled interfaces ha0 8000.d89d672be59d no bond1 dscYvm1_HA0 dscYvm2_HA0 dscYvm3_HA0 imf0 8000.d89d672dc89e no dscYvm1_IMF0 dscYvm2_IMF0 dscYvm3_IMF0 eth6.10 imf1 8000.d89d672dc89f no dscYvm1_IMF1 dscYvm2_IMF1 dscYvm3_IMF1 eth7.11 mgt0 8000.d89d672be59c no dscYvm1_MGT0 dscYvm2_MGT0 dscYvm3_MGT0 eth0 mgt1 8000.d89d672dc89c no dscYvm1_MGT1 dscYvm2_MGT1 dscYvm3_MGT1 eth4 pkt0 8000.d89d672be59e no dscYvm1_PKT0 dscYvm2_PKT0 dscYvm3_PKT0 eth2 pkt1 8000.d89d672be59f no dscYvm1_PKT1 dscYvm2_PKT1 dscYvm3_PKT1 eth3 pkt2 8000.d89d672dc89e no dscYvm1_PKT2 dscYvm2_PKT2 dscYvm3_PKT2 eth6 pkt3 8000.d89d672dc89f no dscYvm1_PKT3 dscYvm2_PKT3 dscYvm3_PKT3 eth vm 8000.fe1fa1bfbfbc no dscYvm1_VM dscYvm2_VM dscYvm3_VM
Overview
Content Tools