[asterisk-users] busy hangup HDLC Bad FCS (8) on Primary D-channel

[randall]

On 06/01/2011 05:42 PM, Tzafrir Cohen wrote:
> On Wed, Jun 01, 2011 at 04:10:34PM +0200, randall wrote:
>> On 06/01/2011 03:55 PM, randall wrote:
>>> On 06/01/2011 03:41 PM, Tzafrir Cohen wrote:
>>>> On Wed, Jun 01, 2011 at 08:06:02AM +0200, randall wrote:
>>>>> Hi all,
>>>>>
>>>>> After running fine for a few months now asterisk seems to hang
>>>>> frequently , still functioning but the DAHDI channels seem busy  (users
>>>>> report a busy signal when calling or being called)
>>>>>
>>>>> A reboot will allow it to run for another day or maybe 2  or 3 till the
>>>>> problem occurs again.
>>>>>
>>>>>
>>>>> running stock Asterisk 1.6.2.9-2+squeeze2 on Debian with stock kernel
>>>>> 2.6.32-5-686
>>>>>
>>>>> i get the following errors:
>>>>> pri_dchannel: PRI got event: HDLC Bad FCS (8) on Primary D-channel of span 2
>>>>>
>>>>> (happens on all 4 spans)
>>>>>
>>>>> and the following in dmesg:
>>>>> [ 9004.635323] NOTICE-xpd_bri: XBUS-00/XPD-01: D-Chan RX DROP: BADFCS: 252
>>>>> [ 9004.635332] NOTICE-xpd_bri: XBUS-00/XPD-01: D-Chan RX:    current
>>>>> packet[0..2]: 55 55 FC
>>>>> [ 9004.635340] NOTICE-xpd_bri: XBUS-00/XPD-01: Multibyte Drop: errno=-71
>>>>>
>>>>>
>>>>> Channel 0/1, span 1 got hangup, cause 18
>>>>
>>>> Is this happening in the middle of a call? Or only a while after the
>>>> call ended?
>>>>
>>>
>>> the "bad fcs" messages seem to happen random
>> there seems to be a relation indeed, have seen them happen randomly
>> quite spurious, but they indeed tend to happen a while after the call is
>> made.
> 
> A while after a call is made? A while after a call is ended?

kept an eye on this and it seems to happen after a call is ended (+- 25
- 30 seconds) and only when dialed out, but not when another call is in
progress.


> 
> Maybe the provider intentionally sets layer 1 down ("to save power")?
sounds logical with the behaviour mentioned above

> 
> That makes sense on PtMP, though I was not aware of this being used on
> PtP.
> 
i'm clueless on this, telco is China Unicom btw