Chapter 1 Cluster
A cluster is implemented through HGMP V2. By employing huawei group management protocol (HGMP V2), a network administrator can manage multiple switches using the public IP address of a switch known as a management device. The switches under the management of the management device are member devices. The management device, along with the member devices, forms a cluster. Normally, a cluster member device is not assigned a public IP address. Management and maintenance operations intended for the member devices in a cluster are redirected by the management device. Figure 1-1illustrates a typical cluster implementation.
Figure 1-1 Diagram for cluster
HGMP V2 offers the following advantages:
l The procedures to configure multiple switches remarkably simplified. When the management device is assigned a public IP address, you can configure/manage a specific member device on the management device instead of logging into it in advance.
l Functions of topology discovery and display provided, which assist network monitoring and debugging
l Software upgrading and parameter configuring can be performed simultaneously on multiple switches.
l Free of topology and distance limitations
l Saving IP address resource
HGMP V2 is comprised of the following three protocols:
l Neighbor discovery protocol (NDP): HGMP V2 implements NDP to discover the information about the directly connected neighbor devices, including device type, software/hardware version, connecting port and so on. The information such as device ID, port mode (duplex or half duplex), product version, and BootROM version can also be given.
l Neighbor topology discovery protocol (NTDP): HGMP V2 implements NTDP to collect the information about the network topology, including the device connections and the device information in the network. The hop range for topology discovery can be adjusted manually.
l Cluster management protocol: The cluster management protocol provides the member recognition and member management function. It cal also perform large-scaled device management together with the network administrator. Member recognition means that the management device recognizes each member in the cluster through locating each member and then distributes the configuration and management commands to members. Member management means to manage the following events through the management device, including adding a member, removing a member, and the member’s authentication on the management device. Member management also manages the cluster parameters including interval of sending handshake packets, management VLAN of the cluster, public FTP server of the cluster.
Cluster-related configurations are described in the following sections.
NDP is the protocol for discovering the information about the adjacent nodes. NDP operates on the data link layer, so it supports different network layer protocols.
NDP is used to discover the information about directly connected neighbors, including the device type, software/hardware version, and connecting port of the adjacent devices. It can also provide the information concerning device ID, port simplex/duplex status, product version, BootROM version and so on.
An NDP-enabled device maintains an NDP information table. Each entry in an NDP table ages with time. You can also clear the current NDP information manually to have adjacent information collected again.
An NDP-enabled device broadcasts NDP packets regularly to all ports in up state. An NDP packet carries the holdtime field, which indicates the period for the receiving devices to keep the NDP data. Receiving devices only store the information carried in the received NDP packets rather than forward them. The corresponding data entry in the NDP table is updated when the received information is different from the existing one. Otherwise, only the holdtime of the corresponding entry is updated.
NTDP is a protocol for network topology information collection. NTDP provides the information about the devices that can be added to clusters and collects the topology information within the specified hops for cluster management.
Based on the NDP information table created by NDP, NTDP transmits and forwards NTDP topology collection request to collect the NDP information and neighboring connection information of each device in a specific network range for the management device or the network administrator to implement needed functions.
Upon detecting a change occurred on a neighbor, a member device informs the management device of the change through handshake packets. The management device then collects the specified topology information through NTDP. Such a mechanism enables topology changes to be tracked in time.
As for NTDP implementing, you need to perform configurations on the management device, the member devices, and the candidate devices as follows:
l On the management device, enable NTDP both globally and for specific ports, and configure the NTDP settings.
l On each member device and candidate device, enable NTDP both globally and for specific ports. As member devices and candidate devices adopt the NTDP settings configured for the management device, NTDP setting configurations are not needed.
l NTDP takes effect in the management VLAN only. S7500 series Ethernet switches take VLAN 1 as the management VLAN, that is, the NTDP function of the S7500 series takes effect in VLAN 1 only.
1.1.4 Introduction to Cluster
I. Introduction to cluster configuration
A cluster has one (and only one) management device. Note the following when creating a cluster:
l You need to designate the management device first. The management device of a cluster is the portal of the cluster. That is, any operations performed in external networks and intended for the member devices of a cluster, such as accessing, configuring, managing, and monitoring, can only be implemented through the management device.
l The management device of a cluster recognizes and controls all the member devices in the cluster, no matter where they are located on the network or how they are connected.
l The management device collects topology information about all the member and candidate devices to provide useful information for users to establish a cluster.
l A management device manages and monitors the devices in the cluster by collecting and processing NDP/NTDP packets. NDP/NTDP packets contain network topology information.
All the above-mentioned operations need the support of the cluster function.
You need to enable the cluster function and configure cluster parameters on a management device. However, you only need to enable the cluster function on the member devices and candidate devices.
II. Introduction to function of cluster
Cluster provides the function of batch management for the switches in the network. Cluster provides external management and maintenance applications, including SNMP, command line, program and data loading, log report and alarm report. These applications can be divided into internal-to-external applications and external-to-internal applications. All the applications are processed according to the following procedure:
l The communication between the management device and member device in the cluster is implemented through packet interaction in the management VLAN.
l The communication between the cluster and the external server is implemented by the Layer 3 interface of the cluster management VLAN.
l When the member device in the cluster communicates with the external server, the member device transmits the data to the management device first, and then the management device transmits the data to the external server. When the management program running on the external server manages the member device, the external server transmits the protocol packets to the management device first, and then the management device forwards the protocol packets to the member device.
You can configure public FTP servers, TFTP servers, logging hosts and SNMP hosts for the whole cluster. The management device in the cluster is the default public FTP server of the cluster when the public FTP server of the cluster is not configured. Cluster, together with the network management system, can perform large-scaled device management.
The S7500 series manage the cluster with VLAN 1 being the management VLAN in the cluster. You are required to configure the IP address of the Layer 3 virtual interface of the management VLAN before setting up a cluster. Otherwise, the cluster cannot be set up successfully. After the cluster is set up, you are not allowed to modify the IP address of the management VLAN interface.
According to their functions and status in a cluster, switches in the cluster play different roles. You can specify the role a switch plays. A switch also changes its role according to specific rules.
The following three switch roles exist in a cluster: management device, member device, and candidate device.
Table 1-1 Switch roles in the cluster
|
Role |
Configuration |
Description |
|
Management device |
l Configured with a public IP address.
l Receive management commands that a user sends through the public network and process the received commands |
l Provide management interfaces for all switches in the cluster
l Manage member devices by redirecting commands, that is, forward the commands to the intended member devices for processing
l Provide the following functions, including neighbor discovery, topology information collection, cluster management, and cluster state maintenance, and support all types of FTP servers and SNMP host proxies |
|
Member device |
Normally, a member device is not configured with a public IP address |
l Member in the cluster
l Neighbor discovery, being managed by the management device, running commands forwarded by proxies, and failure/log reporting |
|
Candidate device |
Normally, a candidate device is not configured with a public IP address |
A candidate device is a switch that does not belong to any cluster, although it can be added to a cluster |
The switch roles are switched according to the following rules:
Figure 1-2 Role switching roles
l Each cluster has one (and only one) management device. A management device collects NDP/NTDP information to discover and determine candidate devices, which can be then added into the cluster through manual configurations.
l A candidate device becomes a member device after being added to a cluster.
l A member device becomes a candidate device after being removed from the cluster.
1.2 Management Device Configuration
Table 1-2 Management device configuration tasks
Table 1-3 Enable NDP globally and for a specific port
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enable NDP globally |
ndp enable |
Required
By default, NDP is enabled globally |
|
Enable NDP for the specified Ethernet ports |
In system view |
ndp enable interface port-list |
You must choose one of them
By default, NDP is enabled on the port |
|
In Ethernet port view |
Enter Ethernet port view |
interface interface-type interface-number |
|
Enable NDP on the port |
ndp enable |
Table 1-4 Configure NDP-related parameters
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Configure the holdtime of NDP information |
ndp timer aging aging-in-seconds |
Optional
By default, the aging time of NDP packets is 180 seconds |
|
Configure the interval to send NDP packets |
ndp timer hello seconds |
Optional
By default, the interval of sending NDP packets is 60 seconds |
Table 1-5 Enable NTDP globally and for specific ports
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enable NTDP globally |
ntdp enable |
Required |
|
Enter Ethernet port view |
interface interface-type interface-number |
— |
|
Enable NTDP for the Ethernet port |
ntdp enable |
Required |
Table 1-6 Configure NTDP parameters
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Configure the range topology information within which is to be collected |
ntdp hop hop-value |
Optional
By default, the hop range for topology collection is 3 hops |
|
Configure the hop delay to forward topology-collection request packets |
ntdp timer hop-delay time |
Optional
By default, the delay of the device is 200 ms |
|
Configure the port delay to forward topology collection request packets |
ntdp timer port-delay time |
Optional
By default, the port delay is 20 ms |
|
Configure the interval to collect topology information |
ntdp timer interval-in-minutes |
Optional
By default, the interval of topology collection is 0. |
|
Quit system view. |
Quit |
— |
|
Start topology information collection |
ntdp explore |
Optional |
Table 1-7 Enable the cluster function
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enable the cluster function globally |
cluster enable |
Optional
By default, the cluster function is enabled |
I. Creating a cluster and configuring cluster parameters manually
Table 1-8 Configure cluster parameters manually
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enter VLAN interface view |
interface Vlan-interface vlan-id |
Required
The S7500 series requires you to configure the IP address of the Layer 3 virtual interface of VLAN1 before you set up a cluster. Otherwise, the cluster cannot be set up. |
|
Configure the IP address of the VLAN interface |
ip address ip-address { mask | mask-length } |
Required |
|
Enter cluster view |
cluster |
— |
|
Configure an IP address pool for the cluster |
ip-pool administrator-ip-address { ip-mask | ip-mask-length } |
Required |
|
Build a cluster |
build name |
Optional
The name argument is the name to be assigned to the cluster. |
|
Configure the holdtime for a switch |
holdtime seconds |
Optional
By default, the holdtime is 60 seconds |
|
Set the interval to send handshake packets |
timer interval |
Optional
By default, the interval to send handshake packets is 10 seconds |
|
Quit cluster view |
quit |
— |
II. Building a cluster automatically
Table 1-9 Enable the cluster function automatically
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enter VLAN interface view |
interface Vlan-interface vlan-id |
Required
The S7500 series requires you to configure the IP address of the Layer 3 virtual interface of VLAN1 before you set up a cluster. Otherwise, the cluster cannot be set up. |
|
Configure the IP address of the VLAN interface |
ip address ip-address { mask | mask-length } |
Required |
|
Enter cluster view |
cluster |
— |
|
Configure the rang e of the IP addresses of the cluster |
ip-pool administrator-ip-address { ip-mask | ip-mask-length } |
Required |
|
Build a cluster automatically |
auto-build [ recover ] |
Optional
You can build clusters according to corresponding prompts |
Table 1-10 Configure interaction for the cluster
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enter cluster view |
cluster |
Required |
|
Configure the public FTP server for the cluster |
ftp-server ip-address |
Optional |
|
Configure the TFTP server for the cluster |
tftp-server ip-address |
Optional |
|
Configure the logging host for the cluster |
logging-host ip-address |
Optional |
|
Configure the SNMP host for the cluster |
snmp-host ip-address |
Optional |
1.3 Member Device Configuration
Table 1-11 Member device configuration tasks
Table 1-12 Enable NDP globally and for specific ports
|
Operation |
Command |
Description |
|
Enter system view |
system-view |
— |
|
Enable NDP globally |
ndp enable |
Required |
