diff --git a/home.admin/_bootstrap.sh b/home.admin/_bootstrap.sh
index 2645feeb7..9bfb50108 100755
--- a/home.admin/_bootstrap.sh
+++ b/home.admin/_bootstrap.sh
@@ -897,8 +897,10 @@ else
   ################################
   # LND and Blockchain Errors will be still in systemd journals
 
-  # /mnt/hdd/bitcoin/debug.log
-  rm /mnt/hdd/${network}/debug.log 2>/dev/null
+  # limit debug.log to 10MB on start - see #3872
+  if [ $(grep -c "shrinkdebugfile=" < /mnt/hdd/bitcoin/bitcoin.conf) -eq 0 ];then
+    echo "shrinkdebugfile=1" | sudo tee -a /mnt/hdd/bitcoin/bitcoin.conf
+  fi
   # /mnt/hdd/lnd/logs/bitcoin/mainnet/lnd.log
   rm /mnt/hdd/lnd/logs/${network}/${chain}net/lnd.log 2>/dev/null
   # https://github.com/rootzoll/raspiblitz/issues/1700