diff --git a/linux_hardening.md b/linux_hardening.md
index 731fc3c..17740dc 100644
--- a/linux_hardening.md
+++ b/linux_hardening.md
@@ -93,9 +93,12 @@ sudo smartctl -a /dev/sda | grep SCT
 SCT capabilities: 	       (0x1081)	SCT Status supported.
 ```
 
+ERC settings: `smartctl -l scterc /dev/sda` or setting `smartctl -l scterc,150,150 /dev/sda`
+
 #### related issues
  - https://gitlab.com/cryptsetup/cryptsetup/-/issues/632 xxHASH64 support, needs separate `--tag-size 8`
  - https://gitlab.com/cryptsetup/cryptsetup/-/issues/668 dm-integrity documentation with setting recommendation
  - https://gitlab.com/cryptsetup/cryptsetup/-/issues/620 systemd LUKS key mgmnt integration
  - https://gitlab.com/cryptsetup/cryptsetup/-/issues/573 issues with caching the flag "recalculating"
  - https://raid.wiki.kernel.org/index.php/Drive_Data_Sheets#Non-Raid_drives 
+ - https://www.smartmontools.org/wiki/FAQ#WhatiserrorrecoverycontrolERCandwhyitisimportanttoenableitfortheSATAdisksinRAID
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diff --git a/reverse_engineering.md b/reverse_engineering.md
new file mode 100644
index 0000000..e23e788
--- /dev/null
+++ b/reverse_engineering.md
@@ -0,0 +1,33 @@
+# reverse engineering
+## radare2
+#### basic file info
+```
+    i           show file information
+    ih          show headers
+    ie          show entry point
+    ii          show imports
+    iE          show exports
+    izz |less   show strings (in less)
+```
+preparing the binary
+```
+    aaaa        analyze binary
+    afl         analyze function list [correspond to ii, iE]
+    pdf         print dissambly function
+```
+```
+    s           search
+    V           enter visual mode
+```
+### visual mode general keys
+```
+    ?           show help
+    p/P         toggle print mode
+    <space>     toggle ascii graph
+    :           open radare2 prompt
+    q           quit
+```
+
+
+###
+[Terminus Project](http://terminus.rewolf.pl/terminus/)
\ No newline at end of file