diff --git a/openbsc/src/libcommon/gsm_data.c b/openbsc/src/libcommon/gsm_data.c
index 352700a..4ccb820 100644
--- a/openbsc/src/libcommon/gsm_data.c
+++ b/openbsc/src/libcommon/gsm_data.c
@@ -408,6 +408,7 @@
 	bts->si_common.chan_desc.att = 1; /* attachment required */
 	bts->si_common.chan_desc.bs_pa_mfrms = RSL_BS_PA_MFRMS_5; /* paging frames */
 	bts->si_common.chan_desc.bs_ag_blks_res = 1; /* reserved AGCH blocks */
+	bts->si_common.chan_desc.t3212 = 5; /* Use 30 min periodic update interval as sane default */
 
 	llist_add_tail(&bts->list, &net->bts_list);