diff --git a/ISEN/Cloud Computing/CIPA4/Cloud Computing Cours 2.md b/ISEN/Cloud Computing/CIPA4/Cloud Computing Cours 2.md
index 34c4e6a..79e9514 100644
--- a/ISEN/Cloud Computing/CIPA4/Cloud Computing Cours 2.md	
+++ b/ISEN/Cloud Computing/CIPA4/Cloud Computing Cours 2.md	
@@ -39,4 +39,32 @@ Q: which IP addres the router is having as external gateway?
 openstack server create --image 'Debian 12' --flavor small --network private --key-name isen myvm01
 ```
 Q: can you access to your instance in SSH?
+No
 
+### Floating IP
+```bash
+openstack server add floating ip myvm01 51.91.90.76
+```
+Q: what IP can you see on ens3 interface of the instance?
+```Bash
+debian@myvm01:~$ ip a
+1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
+    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
+    inet 127.0.0.1/8 scope host lo
+       valid_lft forever preferred_lft forever
+    inet6 ::1/128 scope host noprefixroute 
+       valid_lft forever preferred_lft forever
+2: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc fq_codel state UP group default qlen 1000
+    link/ether fa:16:3e:89:ad:33 brd ff:ff:ff:ff:ff:ff
+    altname enp0s3
+    inet 192.168.42.82/24 metric 100 brd 192.168.42.255 scope global dynamic ens3
+       valid_lft 86313sec preferred_lft 86313sec
+    inet6 fe80::f816:3eff:fe89:ad33/64 scope link 
+       valid_lft forever preferred_lft forever
+```
+
+## Userdata
+### Start an instance
+```bash
+openstack server create --image 'Debian 12' --flavor small --network private --key-name isen --user-data postinstall.sh myvm01
+```