From 54a543d5ea3a58aee2f001498376127efea24bd2 Mon Sep 17 00:00:00 2001 From: Colin Percival Date: Fri, 9 Aug 2024 16:55:30 -0700 Subject: [PATCH] EC2: Set dhclient_arpwait="NO" The DHCP server in EC2 knows exactly which system should be using which IP address (and in fact EC2 has source IP filtering on by default) so there's no point ARPing an address before using it. The preceding commits (changing the ARP wait time from 2 s to 250 ms) and this one (eliminating the wait entirely in EC2) reduce the time required for a newly launched FreeBSD/EC2 instance to launch by 2 seconds. Discussed with: icattard MFC after: 10 days Sponsored by: Amazon --- release/tools/ec2-base.conf | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/release/tools/ec2-base.conf b/release/tools/ec2-base.conf index f4c46fe285c..d80035e11ed 100644 --- a/release/tools/ec2-base.conf +++ b/release/tools/ec2-base.conf @@ -26,6 +26,11 @@ vm_extra_pre_umount() { # requires accept_rtadv. echo 'ifconfig_DEFAULT="SYNCDHCP accept_rtadv"' >> ${DESTDIR}/etc/rc.conf + # The EC2 DHCP server can be trusted to know whether an IP address is + # assigned to us; we don't need to ARP to check if anyone else is using + # the address before we start using it. + echo 'dhclient_arpwait="NO"' >> ${DESTDIR}/etc/rc.conf + # Enable IPv6 on all interfaces, and spawn DHCPv6 via rtsold echo 'ipv6_activate_all_interfaces="YES"' >> ${DESTDIR}/etc/rc.conf echo 'rtsold_enable="YES"' >> ${DESTDIR}/etc/rc.conf