I am getting my WAN IP address from the ISP via DHCP. The WAN interface configuration is as follows:
set interfaces ethernet eth0 address ‘dhcp’
set interfaces ethernet eth0 description ‘WAN’
set interfaces ethernet eth0 duplex ‘auto’
set interfaces ethernet eth0 firewall in name ‘WAN-in’
set interfaces ethernet eth0 firewall local name ‘WAN-local’
set interfaces ethernet eth0 firewall out name ‘WAN-out’
set interfaces ethernet eth0 hw-id ‘52:54:00:37:d0:bc’
set interfaces ethernet eth0 smp-affinity ‘auto’
set interfaces ethernet eth0 speed ‘auto’
I am getting an address as expected, the lease time is one hour:
matze@mewdemstr1# run sh dhcp client leases
interface : eth0
ip address : [redacted] [Active]
subnet mask: 255.255.252.0
domain name: upc.de [overridden by domain-name set using CLI]
router : 176.198.148.1
name server: 80.69.96.12 81.210.129.4
dhcp server: 10.202.232.1
lease time : 3600
last update: Sat Aug 24 03:56:58 CEST 2019
expiry : Sat Aug 24 04:56:57 CEST 2019
reason : RENEW
However, the VyOS DHCP client schedules the renewal too early, at seemingly random intervals:
matze@mewdemstr1:~$ sh log | grep dhclient
Aug 24 03:27:55 mewdemstr1 dhclient[2536]: Removed stale PID file
Aug 24 03:27:55 mewdemstr1 dhclient[2539]: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Aug 24 03:27:55 mewdemstr1 dhclient[2549]: DHCPACK from 10.202.232.1
Aug 24 03:27:58 vyos dhclient[2549]: bound to [redacted] – renewal in 837 seconds.
Aug 24 03:41:55 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
Aug 24 03:42:02 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
Aug 24 03:42:13 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
Aug 24 03:42:25 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
[…]
Aug 24 03:56:42 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
Aug 24 03:56:57 mewdemstr1 dhclient[2549]: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Aug 24 03:56:57 mewdemstr1 dhclient[2549]: DHCPACK from 10.202.232.1
Aug 24 03:56:58 vyos dhclient[2549]: bound to [redacted] – renewal in 1391 seconds.
Aug 24 04:20:09 vyos dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
Aug 24 04:20:14 vyos dhclient[2549]: DHCPREQUEST on eth0 to 10.202.232.1 port 67
[…]
Why is that? Obviously, I’d like the client to request a new lease at an appropriate time…