diff --git a/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_device_tbl.c b/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_device_tbl.c
index cb3814599d36..99d55ee3b2e6 100644
--- a/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_device_tbl.c
+++ b/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_device_tbl.c
@@ -449,7 +449,8 @@ devd_socket_callback(int fd, void *arg __unused)
 
 	HRDBG("called");
 
-	read_len = read(fd, buf, sizeof(buf) - 1);
+again:
+	read_len = read(fd, buf, sizeof(buf));
 	if (read_len < 0) {
 		if (errno == EBADF) {
 			devd_sock = -1;
@@ -476,16 +477,9 @@ devd_socket_callback(int fd, void *arg __unused)
 		syslog(LOG_ERR, "Closing devd_fd, revert to devinfo polling");
 
 	} else {
-		switch (buf[0]) {
-		case '+':
-		case '-':
-		case '?':
-		case '!':
-			refresh_device_tbl(1);
-			return;
-		default:
-			syslog(LOG_ERR, "unknown message from devd socket");
-		}
+		if (read_len == sizeof(buf))
+			goto again;
+		refresh_device_tbl(1);
 	}
 }