Format Of The Mirror Header Attributes; 8-Byte Format - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - POLICY MANAGEMENT CONFIGURATION GUIDE 2010-10-04 Configuration Manual

Format of the Mirror Header Attributes

Copyright © 2010, Juniper Networks, Inc.
Table 57: Prepended Header Field Descriptions (continued)
Field
Source Address
Destination Address
UDP Header
Source Port
Destination Port
Length
Checksum
Mirror Header
MHV (mirror header value)
Mirror Identifier
Session-ID
The mirror header values are determined by the value that you configure in VSA 26-59.
VSA 26-59 is declared as a hexadecimal string that can be either 8 bytes or 4 bytes long.
The 8-byte format enables you to further specify the value that is used for the Session-ID
field. If you use the 4-byte format, the router automatically determines the Session-ID
field. The value in the 2-bit version field specifies the format that is used—0 indicates
the 8-byte format, and 1 indicates the 4-byte format.

8-Byte Format

The 8-byte format of VSA 26-59 enables you to manually specify the Session-ID value
in addition to the Mirror Identifier value. To use the 8-byte format, you configure the first
two most significant bits of the first word of the VSA to a value of 0, which indicates two
words in the VSA. The remaining 30 bits of the first word form the Mirror Identifier value,
and the second word is the Session-ID field. You cannot change the order of these two
words.
For example, a value of 0000030000000090 in VSA 26-59 configures the following
fields in the mirror header, as shown in Figure 23 on page 246:
MHV = 0
Chapter 13: Managing Packet Mirroring
Value
Analyzer interface IP address
VSA 26-60
VSA 26-61
VSA 26-61
Dynamically computed
0
0
See "Format of the Mirror
Header Attributes" on
page 245 for details
See "Format of the Mirror
Header Attributes" on
page 245 for details
Length (Bits)
32
32
16
16
16
16
2
30
32
245