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Serial ports up, but multilink down

I have three serial ports, each a T1 link, that are showing up/up. I've bundled the three into a single multilink interface. The multilink is showing down/down. Debugging ppp authentication doens't show any problems. "show ppp multilink" shows no active bundles, and all three serial links are listed as inactive, along with the multilink.

Looking at each serial port, each is showing "Encapsulation PPP, LCP Open, multilink closed". I've double-checked each serial ports multilink group settings, and they match the multilink interfaces group number.

I can post the config, but it's very basic, with no fancy tricks. It's a very simple Internet-facing router, w/o any routing protocols, only a single default route, and no access lists applied anywhere.

I'd appreciate any ideas on this. Thanks.

Reply to
ttripp
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Yeah, we'd probably need to see the config. It should be real simple. It doesn't take much to do this sort of setup. I'm guessing that you don't tag each T1 interface as 'ppp multilink' to have each PPP link in its PPP startup to start doing multilink negotiation.

This is from a working config.

int Multilink1 ip address ... ppp multilink ppp multilink group 1 int Serial 1/0/1:0 encaps ppp ppp multilink ppp multilink group 1 int Serial 1/0/2:0 encaps ppp ppp multilink ppp multilink group 1 int Serial 1/0/3:0 encaps ppp ppp multilink ppp multilink group 1

Reply to
Doug McIntyre

conf t int multilink1 no shutdown

just a guess?

Reply to
Artie Lange

Nope, that was the first thing I tried.

Reply to
ttripp

Turns out our ISP (Sprint) never turned on multilink on their side. Link came up very quickly once they did. Thanks for the help, all.

Reply to
ttripp

"Oh! you wanted to use that circuit? OK one sec..."

Is that how the call went?

Reply to
Artie Lange

They had the circuits turned up, but not bundled. For once, I had a telco actually listen to the problem and jump right on it, instead of trying to push it back on me or the LEC. Very quick turn-around, and I was up in 15 minutes.

Reply to
ttripp

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