R2511-HP MSR Router Series Layer 3 - IP Services Command Reference(V5)

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Usage guidelines
A NAT entry is not permanent. You can use this command to configure NAT aging time for TCP, UDP,
ICMP, and other protocols. If a NAT entry is not used within the configured time, it will be aged out. For
example, when a user with IP address 10.110.10.10 and port number 2000 establishes an external TCP
connection, NAT assigns an IP address and a port number for the user. If, within a preconfigured aging
time, the TCP connection is not used, the system removes it.
In NO-PAT mode, if the private network is big and the users frequently go online and offline, you can set
a smaller aging time to speed up the release of addresses.
Examples
# Set the NAT aging time for TCP to 240 seconds.
<Sysname> system-view
[Sysname] nat aging-time tcp 240
Related commands
display nat aging-time
nat alg
Use nat alg to enable NAT application layer gateway for one or more protocols.
Use undo nat alg to disable NAT application layer gateway.
Syntax
nat alg { all | dns | ftp | h323 | ils | nbt | pptp | sip }
undo nat alg { all | dns | ftp | h323 | ils | nbt | pptp | sip }
Default
NAT application layer gateway is enabled.
Views
System view
Default command level
2: System level
Parameters
all: Supports all special protocols.
dns: Supports DNS.
ftp: Supports FTP.
h323: Supports H.323.
ils: Supports ILS.
nbt: Supports NBT.
pptp: Supports PPTP.
sip: Supports SIP.
Examples
# Enable NAT application layer gateway for FTP.
<Sysname> system-view