Updating configuration settings about devices

WalT allows users to show or modify device configuration settings by using commands walt device config or walt node config. For instance:

$ walt device config switch1                    # show
$ walt device config switch1 lldp.explore=true  # modify
$ walt node config virt-node ram=384M           # modify

One may also show or change several settings at once, and/or show or update them on several devices at once. (See also: walt help show device-sets) For instance:

$ walt device config all-switches               # show
$ walt device config all-switches lldp.explore=true poe.reboots=true
$ walt node config virt-node-1,virt-node-2 ram=384M

However, in some cases, the semantic of a particular setting may restrict syntax. For instance, the expose setting can only be applied to a single device at once, because it would otherwise mean redirecting a single server TCP port to several devices, an impossible operation.

You can also use this command to indicate to walt server that an unknown device is actually a switch:

$ walt device config unknown-a2f2d3 type=switch

Here is the set of settings currently allowed:

Name

possible values

Applies to:

Notes

boot.delay

e.g. 2 or ‘random’

virtual nodes

boot.retries

e.g. 0 or 9

virtual nodes

boot.timeout

e.g. ‘none’ or 180

nodes

cpu.cores

e.g. 1 or 4

virtual nodes

disks

e.g. ‘8G’ or ‘32G,1T’

virtual nodes

expose

e.g. ‘80:8080,443:8443’

devices of walt-net

kexec.allow

true or false

nodes

lldp.explore

true or false

switches

netsetup

‘NAT’ or ‘LAN’

devices of walt-net

networks

e.g. ‘walt-net,ext-net’

virtual nodes

poe.reboots

true or false

switches

ram

e.g. ‘384M’ or ‘1G’

virtual nodes

snmp.version

1 or 2

switches

snmp.community

e.g. ‘private’

switches

type

‘switch’

‘unknown’ devices

Notes:

  1. See walt help show switch-install

  2. Only allowed when changing device type from ‘unknown’ to ‘switch’

  3. See walt help show device-netsetup

  4. See walt help show vnode-disks

  5. See walt help show vnode-networks

  6. Default is true: allow kexec-rebooting if the optional script [walt-image]:/bin/walt-reboot implements it.

  7. See walt help show device-expose

  8. Settings allowing WalT to detect and automatically hard-reboot nodes failing to boot.

  9. Default is ‘random’, to better share CPU resources when all virtual nodes are started at the same time (server bootup).