diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/etc/dhcp/dhclient-enter-hooks.d/03-vyos-ipwrapper | 53 |
1 files changed, 52 insertions, 1 deletions
diff --git a/src/etc/dhcp/dhclient-enter-hooks.d/03-vyos-ipwrapper b/src/etc/dhcp/dhclient-enter-hooks.d/03-vyos-ipwrapper index 1f27ee14c..7c119b0dd 100644 --- a/src/etc/dhcp/dhclient-enter-hooks.d/03-vyos-ipwrapper +++ b/src/etc/dhcp/dhclient-enter-hooks.d/03-vyos-ipwrapper @@ -1,4 +1,4 @@ -# redefine ip command to use FRR when it is available +# redefine ip command to use FRR when it is available and preserve static addresses # default route distance IF_METRIC=${IF_METRIC:-210} @@ -6,6 +6,43 @@ IF_METRIC=${IF_METRIC:-210} # Check if interface is inside a VRF VRF_OPTION=$(/usr/sbin/ip --json --detail link show ${interface} | jq -r '.[0] | select(.linkinfo.info_slave_kind == "vrf") | "vrf \(.master)"') +# Flush only DHCP (dynamic) addresses from interface, preserving static addresses +# +# When dhclient renews/rebinds a lease, it calls: +# ip -4 addr flush dev <interface> +# This removes ALL IPv4 addresses, including static addresses configured +# via VyOS (e.g., "set interfaces ethernet eth0 address 192.168.1.1/24"). +# +# The ip() wrapper below intercepts the "ip -4 addr flush" command and replaces +# it with a selective flush that only removes addresses marked as "dynamic" by +# the kernel. DHCP-assigned addresses have the "dynamic" flag set automatically. +_flush_dhcp_addrs() { + local dev="${1:-$interface}" + + logmsg info "Selectively flushing only dynamic (DHCP) addresses from ${dev}" + + local addrs + addrs=$(/usr/sbin/ip -4 -j addr show dev "${dev}" 2>&1 | jq -r ' + .[] | .addr_info[]? | select(.family == "inet" and .dynamic == true) + | "\(.local)/\(.prefixlen)" + ' 2>&1) + if [ $? -ne 0 ]; then + logmsg warn "Failed to list dynamic IPv4 addresses on ${dev}; skipping selective flush. ip/jq error output: $addrs" + return 0 + fi + + while IFS= read -r addr; do + if [ -n "$addr" ]; then + logmsg info "Removing dynamic address ${addr} from ${dev}" + if ! /usr/sbin/ip -4 addr del "${addr}" dev "${dev}" 2>&1; then + logmsg warn "Failed to remove dynamic address ${addr} from ${dev}" + fi + fi + done <<< "$addrs" + + return 0 +} + # get status of FRR function frr_alive () { /usr/lib/frr/watchfrr.sh all_status @@ -90,6 +127,20 @@ function vtysh_conf () { # replace ip command with this wrapper function ip () { + # Intercept: ip -4 addr flush dev <interface> + # to preserve static addresses (only remove dynamic/DHCP addresses) + if [ "$1" = "-4" ] && [ "$2" = "addr" ] && [ "$3" = "flush" ]; then + logmsg info "Intercepting 'ip -4 addr flush' to preserve static addresses" + shift 3 + local dev="" + while [ $# -gt 0 ]; do + [ "$1" = "dev" ] && dev="$2" && break + shift + done + _flush_dhcp_addrs "${dev:-$interface}" + return $? + fi + # pass comand to system `ip` if this is not related to routes change if [ "$2" != "route" ] ; then logmsg info "Passing command to /usr/sbin/ip: \"$@\"" |