[rancid] Rancid-discuss Digest, Vol 77, Issue 6

[Alex DEKKER]

On 22/03/17 21:42, Alan McKinnon wrote:
 > On 22/03/2017 22:02, Jones, Herschel wrote:
 >> Alan,
 >>
 >> Crontab here -
 >>
 >> # .---------------- minute (0 - 59)
 >> # |  .------------- hour (0 - 23)
 >> # |  |  .---------- day of month (1 - 31)
 >> # |  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ...
 >> # |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR
 >> sun,mon,tue,wed,thu,fri,sat
 >> # |  |  |  |  |
 >> # *  *  *  *  * user-name  command to be executed
 >>
 >> * 1 * * * /usr/local/rancid/bin/rancid-run #hourly router dump
 >   ^
 > This is your problem. It runs every minute when the hour is "1", 
every minute from 01:00 to 01:59

To the OP - everyone has made this particular mistake at least once :-)

 > The golden rule of cron is you cannot specify intervals like "every 
10 minutes" or "once a day".

Don't want to stray too far off topic here, but "ISC Cron" which 
according to the ever-reliable Wikipedia article is the default cron on 
most Linux and BSDs allows for just this. My RANCID cron entry is:

29 8-22/4 * * * /usr/bin/rancid-run

so at 29 minutes past every 4th hour between 0800 and 2200, it runs. I 
am not sure how this particular frequency was arrived at, but it seems 
to work for us.

alexd