Last two days I have the following issue - every morning there is no connection to ASA5505 and it drops the internet.
My infrastructure is a bit strange - I have ASA5505 which is routing the network, there is no router behind it.
The questions are;
1. Can i use only one ASA5505 without router behind it? I have about 50 PC. Does this slow down performance of ASSA?
2. How can i check what is actually happening behind that problem (logs or something like that)
Yes the 5505 should support 50 PC, you dont need other layer 3 device because it can do that.
Now about the problem, you could verify first the cabling or request assistance from the ISP to verify its device. You can enable the logs on the ASA to verify what is happening.
Also you can make ping (at least 1000 or + pings) to public IP address from the ASA to check connectivity.
Depending on the number of VLANs you have the ASA 5505 should be up to the task of firewalling and inter-VLAN routing. For 50 devices this shouldn't be problem.
What license do you have installed on it? The base license only permits 10 concurrent users on the 'inside'!
If you have a base license, you will find that the outbound connection will probably be working for 10 of them and the other 40 will be reporting that there is no internet connection.
From the config guide:
In routed mode, hosts on the inside (Business and Home VLANs) count towards the limit when they
communicate with the outside (Internet VLAN), including when the inside initiates a connection to the outside as well as when the outside
initiates a connection to the inside. Note that even when the outside initiates a connection
to the inside, outside hosts are not counted towards the limit; only the inside hosts count.
Hosts that initiate traffic between Business and Home are also not counted towards the limit.
The interface associated with the default route is considered to be the outside Internet interface. If there is no default route, hosts on all interfaces are counted toward the limit. In transparent
mode, the interface with the lowest number of hosts is counted towards the host limit.
See the show local-host command to view host limits
You will ned to upgrade to either upgrade to the 50 user license:
...or to the unliited license:
...It is worth noting that the Security Plus license allows unliited users too:
As Seb mentioned it could have 10 concurrent users, please check this link: