diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index c49d8a0939..a3bdf4f40a 100644
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -660,6 +660,54 @@ int dhcp4_set_promote_secondaries(Link *link) {
         return 0;
 }
 
+int dhcp4_set_client_identifier(Link *link) {
+        int r;
+
+        assert(link);
+        assert(link->network);
+        assert(link->dhcp_client);
+
+        switch (link->network->dhcp_client_identifier) {
+        case DHCP_CLIENT_ID_DUID: {
+                /* If configured, apply user specified DUID and/or IAID */
+                const DUID *duid = link_get_duid(link);
+
+                r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
+                                                 link->network->iaid,
+                                                 duid->type,
+                                                 duid->raw_data_len > 0 ? duid->raw_data : NULL,
+                                                 duid->raw_data_len);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m");
+                break;
+        }
+        case DHCP_CLIENT_ID_DUID_ONLY: {
+                /* If configured, apply user specified DUID */
+                const DUID *duid = link_get_duid(link);
+
+                r = sd_dhcp_client_set_duid(link->dhcp_client,
+                                            duid->type,
+                                            duid->raw_data_len > 0 ? duid->raw_data : NULL,
+                                            duid->raw_data_len);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m");
+                break;
+        }
+        case DHCP_CLIENT_ID_MAC:
+                r = sd_dhcp_client_set_client_id(link->dhcp_client,
+                                                 ARPHRD_ETHER,
+                                                 (const uint8_t *) &link->mac,
+                                                 sizeof(link->mac));
+                if (r < 0)
+                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set client ID: %m");
+                break;
+        default:
+                assert_not_reached("Unknown client identifier type.");
+        }
+
+        return 0;
+}
+
 int dhcp4_configure(Link *link) {
         int r;
 
@@ -763,43 +811,5 @@ int dhcp4_configure(Link *link) {
                         return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set listen port: %m");
         }
 
-        switch (link->network->dhcp_client_identifier) {
-        case DHCP_CLIENT_ID_DUID: {
-                /* If configured, apply user specified DUID and/or IAID */
-                const DUID *duid = link_get_duid(link);
-
-                r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
-                                                 link->network->iaid,
-                                                 duid->type,
-                                                 duid->raw_data_len > 0 ? duid->raw_data : NULL,
-                                                 duid->raw_data_len);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m");
-                break;
-        }
-        case DHCP_CLIENT_ID_DUID_ONLY: {
-                /* If configured, apply user specified DUID */
-                const DUID *duid = link_get_duid(link);
-
-                r = sd_dhcp_client_set_duid(link->dhcp_client,
-                                            duid->type,
-                                            duid->raw_data_len > 0 ? duid->raw_data : NULL,
-                                            duid->raw_data_len);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set DUID: %m");
-                break;
-        }
-        case DHCP_CLIENT_ID_MAC:
-                r = sd_dhcp_client_set_client_id(link->dhcp_client,
-                                                 ARPHRD_ETHER,
-                                                 (const uint8_t *) &link->mac,
-                                                 sizeof(link->mac));
-                if (r < 0)
-                        return log_link_error_errno(link, r, "DHCP4 CLIENT: Failed to set client ID: %m");
-                break;
-        default:
-                assert_not_reached("Unknown client identifier type.");
-        }
-
-        return 0;
+        return dhcp4_set_client_identifier(link);
 }
diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 6b870c5bd5..09bc0ac907 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -3435,41 +3435,9 @@ int link_update(Link *link, sd_netlink_message *m) {
                                 if (r < 0)
                                         return log_link_warning_errno(link, r, "Could not update MAC address in DHCP client: %m");
 
-                                switch (link->network->dhcp_client_identifier) {
-                                case DHCP_CLIENT_ID_DUID: {
-                                        const DUID *duid = link_get_duid(link);
-
-                                        r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
-                                                                         link->network->iaid,
-                                                                         duid->type,
-                                                                         duid->raw_data_len > 0 ? duid->raw_data : NULL,
-                                                                         duid->raw_data_len);
-                                        if (r < 0)
-                                                return log_link_warning_errno(link, r, "Could not update DUID/IAID in DHCP client: %m");
-                                        break;
-                                }
-                                case DHCP_CLIENT_ID_DUID_ONLY: {
-                                        const DUID *duid = link_get_duid(link);
-
-                                        r = sd_dhcp_client_set_duid(link->dhcp_client,
-                                                                    duid->type,
-                                                                    duid->raw_data_len > 0 ? duid->raw_data : NULL,
-                                                                    duid->raw_data_len);
-                                        if (r < 0)
-                                                return log_link_warning_errno(link, r, "Could not update DUID in DHCP client: %m");
-                                        break;
-                                }
-                                case DHCP_CLIENT_ID_MAC:
-                                        r = sd_dhcp_client_set_client_id(link->dhcp_client,
-                                                                         ARPHRD_ETHER,
-                                                                         (const uint8_t *)&link->mac,
-                                                                         sizeof(link->mac));
-                                        if (r < 0)
-                                                return log_link_warning_errno(link, r, "Could not update MAC client id in DHCP client: %m");
-                                        break;
-                                default:
-                                        assert_not_reached("Unknown client identifier type.");
-                                }
+                                r = dhcp4_set_client_identifier(link);
+                                if (r < 0)
+                                        return r;
                         }
 
                         if (link->dhcp6_client) {
diff --git a/src/network/networkd-link.h b/src/network/networkd-link.h
index 35e44cd09f..6ed11ff51c 100644
--- a/src/network/networkd-link.h
+++ b/src/network/networkd-link.h
@@ -159,6 +159,7 @@ int link_set_mtu(Link *link, uint32_t mtu);
 
 int ipv4ll_configure(Link *link);
 int dhcp4_configure(Link *link);
+int dhcp4_set_client_identifier(Link *link);
 int dhcp4_set_promote_secondaries(Link *link);
 int dhcp6_configure(Link *link);
 int dhcp6_request_address(Link *link, int ir);