[sr-dev] Safe to change expires column in location table to type timestamp?

[Daniel-Constantin Mierla]

On 11/4/13 4:47 PM, Alistair Cunningham wrote:
> Over the weekend, one of our customers in the USA suffered a mass 
> de-registration of handsets during the daylight saving change. After 
> one registration interval, they all re-registered, but inbound calls 
> failed for one full registration interval of each handset.
>
> The same customer had this happen last year when they were running 
> OpenSIPS. At that time, it was determined by the OpenSIPS developers 
> that the problem was that the "expires" column in the location table 
> (stored in MySQL, with db_mode 3) was of type "datetime", which does 
> not handle daylight saving changes gracefully. They suggested changing 
> the db_mode, but this isn't an option because other software reads the 
> location table in real time to decide which SIP proxy machine the 
> handset is registered to. We discussed changing this column (and 
> last_modified which is also a datetime) to type "timestamp", but our 
> customer switched to Kamailio before we could make a final decision on 
> this.
>
> My question is therefore: can we safely do a MySQL "alter table" 
> command to change these two columns to timestamps so that this problem 
> won't happen again next year?
>
Do you know if mysql accepts to set a timestamp column with a datetime 
value? I will look over the code to see if there are potential side 
effects and eventually some workarounds.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla - http://www.asipto.com
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