diff --git a/net/dns.c b/net/dns.c
index ff9ddffc9d0a1f15e7febf808c5606f69ab48a3d..dd45320150452299e2d2adcdfcd96eb84d06c7f7 100644
--- a/net/dns.c
+++ b/net/dns.c
@@ -202,5 +202,8 @@ DnsStart(void)
 	NetSetTimeout(DNS_TIMEOUT, DnsTimeout);
 	net_set_udp_handler(DnsHandler);
 
+	/* Clear a previous MAC address, the server IP might have changed. */
+	memset(NetServerEther, 0, sizeof(NetServerEther));
+
 	DnsSend();
 }