diff --git a/package/odhcp6c/0002-dhcpv6-use-stable-IAID-for-IA_NA.patch b/package/odhcp6c/0002-dhcpv6-use-stable-IAID-for-IA_NA.patch
new file mode 100644
index 0000000000..fc70205ccc
--- /dev/null
+++ b/package/odhcp6c/0002-dhcpv6-use-stable-IAID-for-IA_NA.patch
@@ -0,0 +1,95 @@
+From 9a4d6fe802d21e4fc1b84f7d55b5c3c23e71d6ba Mon Sep 17 00:00:00 2001
+From: Paul Donald <newtwen+github@gmail.com>
+Date: Thu, 18 Dec 2025 15:10:24 +0100
+Subject: [PATCH] dhcpv6: use stable IAID for IA_NA
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+https://www.rfc-editor.org/rfc/rfc8415.html#section-12
+
+   ........  The IAID is chosen by the client.  For any given use of an
+   IA by the client, the IAID for that IA MUST be consistent across
+   restarts of the DHCP client.  The client may maintain consistency by
+   either storing the IAID in non-volatile storage or using an algorithm
+   that will consistently produce the same IAID as long as the
+   configuration of the client has not changed.
+
+Signed-off-by: Paul Donald <newtwen+github@gmail.com>
+Link: https://github.com/openwrt/odhcp6c/pull/140
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+
+Upstream: https://github.com/openwrt/odhcp6c/commit/9a4d6fe802d21e4fc1b84f7d55b5c3c23e71d6ba
+
+Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
+---
+ src/dhcpv6.c  | 15 +++++++++++++--
+ src/odhcp6c.h |  1 +
+ 2 files changed, 14 insertions(+), 2 deletions(-)
+
+diff --git a/src/dhcpv6.c b/src/dhcpv6.c
+index d8bb8be..97860b1 100644
+--- a/src/dhcpv6.c
++++ b/src/dhcpv6.c
+@@ -262,6 +262,9 @@ static struct dhcpv6_stats dhcpv6_stats = {0};
+ // config
+ static struct config_dhcp* config_dhcp = NULL;
+ 
++// store unique ifname hash to use as IA->IAID
++static uint32_t ifname_hash_iaid = 0;
++
+ static uint32_t ntohl_unaligned(const uint8_t *data)
+ {
+ 	uint32_t buf;
+@@ -542,6 +545,12 @@ void dhcpv6_reset_stats(void)
+ 	memset(&dhcpv6_stats, 0, sizeof(dhcpv6_stats));
+ }
+ 
++uint32_t hash_ifname(const char *s) {
++	uint32_t h = 0;
++	while (*s) h = h * 31 + *s++;
++	return h;
++}
++
+ int init_dhcpv6(const char *ifname)
+ {
+ 	config_dhcp = config_dhcp_get();
+@@ -566,6 +575,8 @@ int init_dhcpv6(const char *ifname)
+ 	if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
+ 		goto failure;
+ 
++	ifname_hash_iaid = hash_ifname(ifname);
++
+ 	ifindex = ifr.ifr_ifindex;
+ 
+ 	// Set the socket to non-blocking mode
+@@ -838,7 +849,7 @@ static void dhcpv6_send(enum dhcpv6_msg req_msg_type, uint8_t trid[3], uint32_t
+ 	struct dhcpv6_ia_hdr hdr_ia_na = {
+ 		.type = htons(DHCPV6_OPT_IA_NA),
+ 		.len = htons(sizeof(hdr_ia_na) - DHCPV6_OPT_HDR_SIZE),
+-		.iaid = htonl(ifindex),
++		.iaid = htonl(ifname_hash_iaid),
+ 		.t1 = 0,
+ 		.t2 = 0,
+ 	};
+@@ -1392,7 +1403,7 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _o_unused const int rc,
+ 						continue;
+ 
+ 					// Test ID
+-					if (ia_hdr->iaid != htonl(ifindex) && otype == DHCPV6_OPT_IA_NA)
++					if (ia_hdr->iaid != htonl(ifname_hash_iaid) && otype == DHCPV6_OPT_IA_NA)
+ 						continue;
+ 
+ 					uint16_t code = DHCPV6_Success;
+diff --git a/src/odhcp6c.h b/src/odhcp6c.h
+index aa73bbc..c57f885 100644
+--- a/src/odhcp6c.h
++++ b/src/odhcp6c.h
+@@ -540,6 +540,7 @@ struct odhcp6c_opt {
+ 	const char *str;
+ };
+ 
++uint32_t hash_ifname(const char *s);
+ int init_dhcpv6(const char *ifname);
+ int dhcpv6_get_ia_mode(void);
+ int dhcpv6_promote_server_cand(void);