Problem with Multilink !!!

[haneo]

Hello,

I have configured a multilink on 7204VXR using four serial connexions

*******
controller E1 2/0
channel-group 0 unframed
!
controller E1 2/1
channel-group 0 unframed
!
controller E1 2/2
channel-group 0 unframed
!
controller E1 2/3
channel-group 0 unframed

interface Multilink1
ip address 10.0.0.1
no cdp enable
ppp multilink
multilink-group 1

interface Serial2/0:0
no ip address
encapsulation ppp
ppp multilink
multilink-group 1
no fair-queue
no cdp enable

interface Serial2/1:0
no ip address
encapsulation ppp
ppp multilink
multilink-group 1
no fair-queue
no cdp enable

interface Serial2/2:0
no ip address
encapsulation ppp
ppp multilink
multilink-group 1
no fair-queue
no cdp enable

interface Serial2/3:0
no ip address
encapsulation ppp
ppp multilink
multilink-group 1
no fair-queue
no cdp enable
******


but when logged on the router, and ping the ip 10.0.0.1 I get more the 200ms !!!

is there any problem with the multilink configuration, or a bug in the CISCO IOS ?

Thank you in advance.

CCNA

 

[JOAMON]

You might try adding the following to your multilink interface:
ppp multilink fragment disable

Also may consider enabling IP CEF per destination if not already enabled.

 

[haneo]

Thanks for the answer,

the IP CEF per destination should by enabled in eatch serial interface, or just only in the multilink interface ?

CCNA

 

[KiscoKid]

Your config doesn't seem complete to me.

Therefore can you confirm what PA adaptor(s) you're using in the 7200. Also can you confirm what the data rate has been provisioned for each E1, i.e. is it 2.048mb or less. Finally can you confirm the physical connection type, i.e. is it BNC, X21.

Thanks

 

[haneo]

I use "8-port Multichannel E1 (G.703/G.704&PRI)"
named : PA-MC-8E1/120

We have leased ligne (2048Mb/s each E1) with our ISP
thx

CCNA

 

[KiscoKid]

The channel-group 0 unframed command in your controller config suggests your telecomms provider has set you up for G.703 framing. The fact you have not specified a clock source further suggests they are providing you with a structured G.703 service.

Can you paste a copy of the 'show interface e1' command.

many thanks

 

[KiscoKid]

Sorry I meant 'show controller e1'

 

[xenolith]

Do you experience the same problem if you remove some of the lines from the bundle? The reason I ask is I had a similar situation. I was providing a 4 T1 multilink group from a 7206VXR (using PA-MC-T3 with channelized T1) to a 3662 (using NM-2W with WIC-2Ts I think, customer router so memory is foggy on it now). Anyway, when we had 3 T1s in the multilink group, things ran fine, but when we added the 4th T1, ping responses shot up to 300ms. The group worked correctly when any 3 were up, but when the 4th was added it would always fail like this. Evantually the NM-2W was replaced and the problem resolved.

No guarantees this is the same situation for you, but it may give you some insight.

I would recommend working with the provider and test each of the E1s seperately and see how this compares. Additionally, you can use HDLC encapsulation and loopbacks to attempt to isolate the problem.

http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00800a70fa.shtml

Good luck!