Big problem in postgres backup

Hi there.

I'm new in using postgres but i've been able to handle my self for a while but now I need some help.

What I want to do is to make automatic backups of my databases once a day at an specific hour. What I did was to login as a postgres user, then use the pg_dumpall and cron commands so I can configure a backup in for example 9:05am every day.

So my sentence was like this:

5 9 * * * pg_dump > /home/admin/bkup.dump


Being bkup.dump the file where the scrip is going to be saved. But every time I try I get and error :

bash: /home/admin/bkup.dump: Permission denied


How can I fix that? If anyone can help me please lend me a hand, I'm new on this matter.

Thanks