Ts is just the old variable name, the remote message id is used for that
field, not a time stamp. So as long as your supplier provides a unique
message ID you won't have collisions
On Tuesday, 01 November 2016, Robert Chen <robert.c...@thorntechnologies.com>
wrote:
> Hi, I'm trying to set up Kannel with Redis. My concern is that some DLRs
> would be lost due to timestamp collisions. And my question is whether
> hard-coding dlr_redis_add to use the destination (at least for my personal
> installation) is the best approach.
>
> dlr_redis.c:
> Changing:
> if (entry->use_dst && entry->destination)
> To this:
> if (entry->destination) { ... }
>
> Here's my train of thought:
>
> I'm load-balancing Kannel. And according to community recommendations,
> each instance is using the same smsc-id:
>
> - http://kannel.6189.n7.nabble.com/How-to-Multiple-SMSC-s-conf
> iguration-and-how-to-Load-balancing-B-W-Muliple-SMSC-s-td17874.html
>
> <http://kannel.6189.n7.nabble.com/How-to-Multiple-SMSC-s-configuration-and-how-to-Load-balancing-B-W-Muliple-SMSC-s-td17874.html>
> - https://francispereira.com/kannel-setting-up-active-active-
> load-balanced-smpp-gateways.html
>
> <https://francispereira.com/kannel-setting-up-active-active-load-balanced-smpp-gateways.html>
> - http://stackoverflow.com/questions/10322269/kannelroute-
> message-through-2-smsc
>
> The current Kannel setup is using 1.4.4 with MySQL. I'm in the process of
> migrating the whole thing to cloud hosting, but using Redis this time.
>
> I'm worried that DLRs could be lost if they come back with the same
> timestamp. Within dlr_redis.c, it looks like it does one of two things:
>
> 1. If the REDIS_PRECHECK flag is set, it uses HSETNX (only creating a key
> if it does not exist)
> 2. Otherwise, it uses HMSET (overriding whatever dictionary is tied to
> that key)
>
> Either way, it looks like one of the DLRs will get lost if there's ever a
> conflict.
>
> Within dlr_redis.c, it looks like the key can be one of two formats:
>
> 1. <table>:<smsc>:<timestamp>
> 2. <table>:<smsc>:<timestamp>:<destination>
>
> After analyzing a MySQL CSV dump containing 1 million messages, I'm
> finding rows with identical timestamps. And for Redis, this could spell a
> key collision. But, I can get all the keys to be unique by including the
> destination.
>
> I'm trying to figure out how to force Kannel to include the destination.
> According to the documentation, it seems like this is determined by the
> SMSC:
>
> “Some SMSCs also append the destination to the DLR keyname resulting DLR
> keynames in the format <table>:<smsc>:<timestamp>:<destination>.”
>
> It seems as though cimd2 and emi are the SMSC types that append the
> destination.
>
> gateway-1.4.4/gw $ grep -iR dlr_add .
> ./smsc/http/clickatell.c: dlr_add(conn->id, msgid, msg, 0);
> ./smsc/http/generic.c: dlr_add(conn->id, msgid,
> msg, 0);
> ./smsc/http/generic.c: dlr_add(conn->id, msgid, msg, 0);
> ./smsc/http/xidris.c: dlr_add(conn->id, mid, msg, 0);
> ./smsc/smsc_at.c: dlr_add(privdata->conn->id,
> dlrmsgid, msg, 0);
> ./smsc/smsc_cgw.c: dlr_add(conn->id, ts, msg, 0);
> ./smsc/smsc_cimd2.c: dlr_add(conn->name, ts, msg, 1);
> ./smsc/smsc_emi.c: dlr_add((conn->id ? conn->id : privdata->name),
> ts, m, 1);
> ./smsc/smsc_fake.c: dlr_add(conn->id, tmp, sms, 0);
> ./smsc/smsc_http.c: dlr_add(conn->id, mid, msg, 0);
> ./smsc/smsc_loopback.c: dlr_add(conn->id, mid, sms, 0);
> ./smsc/smsc_oisd.c: dlr_add(conn->name, ts, msg, 0);
> ./smsc/smsc_smpp.c: dlr_add(smpp->conn->id, tmp, msg,
> 0);
> ./smsc/smsc_soap.c: dlr_add(conn->id, octstr_imm(tmpid), msg, 0);
> ./smsc/smsc_soap_parlayx.c: dlr_add(conn->id, mid, sms, 0);
> ./smsc/smsc_soap_parlayx.c: dlr_add(conn->id, mid, msg, 0);
> The problem though is that I'm using smpp. (I verified against my SMSC
> that the format coming back is indeed <table>:<smsc>:<timestamp>)
>
> So I guess my question is, should I just hard-code my local install to
> append the destination? Or is there a better approach or some configuration
> flat I'm just not seeing?
>
> Thanks!
> Robert Chen
>
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