From ccd1008682a4b08876b5dfb28452caa395faa139 Mon Sep 17 00:00:00 2001 From: Tzafrir Cohen Date: Tue, 8 Feb 2011 13:09:45 +0000 Subject: Fixed up the loss of crc4-multiframe alignment logic Loss of crc4-multiframe alignment on an E1 link is not a condition which brings the span down. The span will continue to run as long as it can maintain double frame alignment. Because of this, we cannot place the LMFA alarm in the usual spaninfo.alarms member, due to userspace programs using this as a catch-all for a span being up or down. We can detect the alarm by watching the frame error counter (fecount). If it continuously increments, the span is configured for crc4, and the span remains OK (alarms = 0), then we are in loss of crc4-multiframe state. In order to test this alarm, you'll need to synthesize a loss of crc4 alignment on the span. You can usually do this by configuring the local span to use crc4 and the remote end to not use crc4. I used the Fireberd 6000 in my lab to do this. dahdi-743 & dahdi-420 Acked-by: Shaun Ruffell Merged revisions 9458 via svnmerge from http://svn.digium.com/svn/dahdi/tools/trunk git-svn-id: http://svn.asterisk.org/svn/dahdi/tools/branches/2.4@9738 a0bf4364-ded3-4de4-8d8a-66a801d63aff --- dahdi_scan.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/dahdi_scan.c b/dahdi_scan.c index 582f44d..1a30d18 100644 --- a/dahdi_scan.c +++ b/dahdi_scan.c @@ -95,11 +95,13 @@ int main(int argc, char *argv[]) strcat(alarms, "YEL/"); if (s.alarms & DAHDI_ALARM_RED) { strcat(alarms, "RED/"); + +/* Extended alarm feature test. Allows compilation with + * versions of dahdi-linux prior to 2.4 + */ #ifdef DAHDI_ALARM_LFA if (s.alarms & DAHDI_ALARM_LFA) strcat(alarms, "LFA/"); - if (s.alarms & DAHDI_ALARM_LMFA) - strcat(alarms, "LMFA/"); #endif /* ifdef DAHDI_ALARM_LFA */ } if (s.alarms & DAHDI_ALARM_LOOPBACK) @@ -115,10 +117,35 @@ int main(int argc, char *argv[]) alarms[strlen(alarms)-1]='\0'; } } else { - if (s.numchans) - strcpy(alarms, "OK"); - else + if (s.numchans) { +#ifdef DAHDI_ALARM_LFA + /* If we continuously receive framing errors + * but our span is still in service, and we + * are configured for E1 & crc4. We've lost + * crc4-multiframe alignment + */ + if ((s.linecompat & DAHDI_CONFIG_CRC4) && + (s.fecount > 0)) { + struct dahdi_spaninfo t; + memset(&t, 0, sizeof(t)); + t.spanno = x; + sleep(1); + if (ioctl(ctl, DAHDI_SPANSTAT, &t)) + continue; + + /* Test fecount at two separate time + * intervals, if they differ, throw LMFA + */ + if ((t.fecount > s.fecount) && + !t.alarms) { + strcat(alarms, "LMFA/"); + } + } +#endif /* ifdef DAHDI_ALARM_LFA */ + strcat(alarms, "OK"); + } else { strcpy(alarms, "UNCONFIGURED"); + } } fprintf(stdout, "[%d]\n", x); -- cgit v1.2.3