Ascend Archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
(ASCEND) Is LQM any good ?
Hi,
we've tried for days to configure a pair of P130/V.35 to provide:
1) A leased line (E1 2Mbps) connected with Primus TA DCE devices.
2) Dial backup for 1) if the leased line fails.
Bad enough, we didn't find a final working solution. The central
problem is detecting a line failure of the leased line. The Pipes
can detect a failure that is signaled by the TAs (by dropping DCD),
but cannot detect more complicated errors. The TAs in question do
not signal AIS with a DCD drop, for instance. Furthermore, a typical
WAN link can be defective in one direction, but still operative in the
other direction. So if one Pipe detects line loss but the other doesn't,
bad things will happen: The one which did detect loss will dial the
other, but that one will yell "LAN security error" because for him,
the primary profile is still active and the backup profile (with same
IP destination) is a call collision. This can get expensive.
==> What we need is working Keep-Alive on the line.
I was under the impression that LQM could provide for this. But I cannot
see any trace of LQM on my PPP link: neither is anything more than basic
LCP stuff negotiated when the line comes up, nor are any frames bounced
between the peers when the link is otherwise idle. I don't see LCP echo
requests or replies. I see nothing. Consequently, a line loss is never
seen by the Pipes.
So what is the LQM option good for if it does _nothing_ ? (6.0.2)
Just FYI, we _had_ to solve the problem and two Cisco 1603 did solve it
perfectly. I'm mostly Cisco illiterate, but it took me 3h straightforward
configuration to get this running, the only hitch beeing to use PPP on
the leased line because Cisco-HDLC keepalive doesn't detect a simplex
line failure correctly while LCP does (echo requests/replies are round-
trips).
Would this be possible with P130s ? How to configure them ? How to provide
for working keepalive that detects simplex failures ?
TIA,
Andre.
--
Kanther-Line: PGP SSH IDEA MD5 GOST RIPE-MD160 3DES RSA FEAL32 RC4
+-o-+--------------------------------------------------------+-o-+
| o | \\\- Brain Inside -/// | o |
| o | ^^^^^^^^^^^^^^ | o |
| o | Andre' Beck (ABPSoft) AB10-RIPE Xlink PoP Dresden | o |
+-o-+--------------------------------------------------------+-o-+
++ Ascend Users Mailing List ++
To unsubscribe: send unsubscribe to ascend-users-request@bungi.com
To get FAQ'd: <http://www.nealis.net/ascend/faq>