Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010 Configuration Manual page 617

ppp max-negotiations
Use to cause the router to ignore a mismatch of the LCP peer magic number and
retain the PPP connection when the peer has not negotiated an LCP magic
number.
For more information about using this command, see "Validation of LCP Peer
Magic Number" on page 265 in "Configuring Point-to-Point Protocol" on page 263.
To verify configuration of LCP peer magic number validation on the router, use
the show profile command. For information, see "show profile" on page 609.
Example
host1(config-if)#ppp magic-number ignore-mismatch
Use the no version to restore the default behavior, in which the router terminates
the PPP connection if it detects an LCP peer magic number mismatch.
See ppp magic-number ignore-mismatch.
Use to configure the maximum number of LCP, IPCP, or IPv6CP renegotiation
attempts, in the range 1–65535, that the router accepts before terminating a
PPP session.
Configuring the maximum number of renegotiation attempts helps avoid massive
renegotiation loops that can occur between the router and a noncompliant PPP
client. Such renegotiation loops can cause excessive CPU utilization and can
prevent the PPP client from coming up properly.
When a PPP client exceeds the configured maximum number of renegotation
attempts, the router sends a termination request to end the PPP session. When
the PPP session is terminated and LCP goes into a stopped (closed) state, dynamic
PPP or MLPPP interface columns are torn down and wait to be recreated when
traffic is detected on the interface.
If you do not specify the optional lcp, ipcp, or ipv6cp keyword, the ppp
max-negotiations command sets the maximum number of renegotiation
attempts for each of LCP, IPCP, and IPv6CP to the value you specify, or to the
default value (30) if you omit the optional value for maximum renegotiation
attempts.
When both IPv4 interface columns and IPv6 interface columns are configured
over a PPP link-layer interface, the router terminates the PPP session only when
the PPP client exceeds the configured maximum number of renegotiation
attempts for both the IPv4 interface and the IPv6 interface.
Example 1 Sets the maximum number of LCP renegotiation attempts to 5
host1(config-profile)#ppp max-negotiations lcp 5
Example 2 Sets the maximum number of IPCP renegotiation attempts to 30
(the default)
host1(config-profile)#ppp max-negotiations ipcp
Example 3 Sets the maximum number of LCP, IPCP, and IPv6CP renegotiation
attempts to 15
Chapter 17: Configuring Dynamic Interfaces
Configuring a Dynamic Interface from a Profile
585