set service dhcpv6-server shared-network-name LAN subnet 2001:db8:ff::/64 static-mapping client1 identifier 'c5b75e23'
results in
Aug 29 16:22:25 LR2 commit: Successful change to active configuration by user cpo on /dev/pts/0 Aug 29 17:04:01 LR2 dhcpd: WARNING: Host declarations are global. They are not limited to the scope you declared them in. Aug 29 17:04:01 LR2 dhcpd: /opt/vyatta/etc/dhcpdv6.conf line 25: c5b75e23 exceeds max (255) for precision. Aug 29 17:04:01 LR2 dhcpd: host-identifier option dhcp6.client-id c5b75e23; Aug 29 17:04:01 LR2 dhcpd: ^ Aug 29 17:04:01 LR2 dhcpd: Configuration file errors encountered -- exiting