Discovering Switches

Use switchdiscover command to discover the switches that are attached to the neighboring subnets on xCAT management node.

switchdiscover [noderange|--range ip_ranges][-s scan_methods][-r|-x|-z][-w]

where the scan_methods can be nmap, snmp”, or **lldp . The default is nmap. (nmap comes from most os distribution.)

To discover switches over the IP range 10.4.25.0/24 and 192.168.0.0/24, use the following command:

# switchdiscover --range 10.4.25.0/24,192.168.0.0/24
Discovering switches using nmap...
ip              name                    vendor                  mac
------------    ------------            ------------            ------------
192.168.0.131   switch_192_168_0_131    Mellanox Technologie    00:02:C9:AA:00:53
10.4.25.1       switch_10_4_25_1        Juniper networks        2C:6B:F5:00:11:22

If -w flag is specified, the command will write the discovered switches into xCAT databases. If the command above was executed with -w the following switch objects would be created:

# lsdef switch_name
Object name: switch_name
groups=switch
ip=switch_ip
mgt=switch
nodetype=switch
switchtype=switch_vendor

The Ip address is stored in the hosts table. You can run the following command to add the IP addresses in the /etc/hosts

makehosts

The discovery process works with the following four kind of switches:

Mellanox (IB and Ethernet switches)
Cisco
BNT
Juniper

The switchdiscover command can display the output in xml format, stanza format and normal list format. See the man pages for this command for details.