ESR series service routers.ESR-Series. User manual
Step Description Command Keys
5 Disable filtration of packets for which it 
was not possible to determine 
belonging to any known connection and 
which are not the beginning of a new 
connection (optional, may reduce the 
performance).
esr(config)# ip firewall sessions 
allow-unknown
6 Select firewall operation mode 
(optional).
In stateful mode, only the first packet of 
the session is checked, and if direct 
traffic is allowed, return traffic is 
allowed automatically.
In stateless mode, each packet is 
checked. Direct and return traffic must 
be allowed in the corresponding zone-
pair (see step 29).
Firewall operation according to the list 
of applications is possible only in 
stateless mode.
esr(config)# ip firewall mode 
<MODE>
<MODE> – firewall operation 
mode, may take the following 
values: stateful, stateless.
Default value: stateful.
7 Determine the session lifetime for 
unsupported protocols (optional).
esr(config)# ip firewall sessions 
generic-timeout <TIME>
<TIME> – session lifetime for 
unsupported protocols, takes 
values in seconds [1..8553600].
Default value: 60 seconds.
8 Determine ICMP session lifetime after 
which it is considered to be outdated 
(optional).
esr(config)# ip firewall sessions 
icmp-timeout <TIME>
<TIME> – ICMP session 
lifetime, takes values in 
seconds [1..8553600].
Default value: 30 seconds.
9 Determine ICMPv6 session lifetime 
after which it is considered to be 
outdated (optional).
esr(config)# ip firewall sessions 
icmpv6-timeout <TIME>
<TIME> – ICMP session 
lifetime, takes values in 
seconds [1..8553600].
Default value: 30 seconds.
10 Determine the size of outstanding 
sessions table (optional).
esr(config)# ip firewall sessions 
max-expect <COUNT>
<COUNT> – table size, takes 
values of [1..8553600].
Default value: 256.
11 Determine the size of trackable 
sessions table (optional).
esr(config)# ip firewall sessions 
max-tracking <COUNT>
<COUNT> – table size, takes 
values of [1..8553600].
Default value: 512000.