Grandstream UCM6100 User Manual for 1.0.9.25 - Manual (Page 71)

Firmware Version 1.0.9.25 UCM6100 Series IP PBX User Manual Page 70 of 303
• If a host at IP address 192.168.40.7 initiates more than 20 TCP connections to the UCM6100 within 1
minute, it will be added into UCM6100 blacklist.
• This host 192.168.40.7 will be blocked by the UCM6100 for 300 seconds.
• Since IP address 192.168.40.5 is in whitelist, if the host at IP address 192.168.40.5 initiates more than
20 TCP connections to the UCM6100 within 1 minute, it will not be added into UCM6100 blacklist. It
can still establish TCP connection with the UCM6100.
Figure 35: Configure Dynamic Defense
FAIL2BAN
Fail2Ban feature on the UCM6100 provides intrusion detection and prevention for authentication errors in
SIP REGISTER, INVITE and SUBSCRIBE. Once the entry is detected within "Max Retry Duration", the
UCM6100 will take action to forbid the host for certain period as defined in "Banned Duration". This feature
helps prevent SIP brute force attacks to the PBX system.
Table 19: Fail2Ban Settings
Global Settings
Enable Fail2Ban
Enable Fail2Ban. The default setting is disabled. Please make sure both "Enable
Fail2Ban" and "Asterisk Service" are turned on in order to use Fail2Ban for SIP
authentication on the UCM6100.
Banned Duration
Configure the duration (in seconds) for the detected host to be banned. The
default setting is 300. If set to -1, the host will be always banned.
Max Retry Duration
Within this duration (in seconds), if a host exceeds the max times of retry as
defined in "MaxRetry", the host will be banned. The default setting is 5.