Setting timezone in AIX

Question

The timezone is set to "CET" but date displays CEST

$ echo TZ
CET
$ date
Tue Apr 16 15:56:57 CEST 2013

Noticed the timezone on another similar system is "CET0" (not sure what the 0 means here!). But date displays the expected timezone:

$ echo $TZ
CET0
$ date
Tue Apr 16 15:51:26 CET 2013

So changed the timezone using chtz CET0 and rebooted. But date now displays UTC!

$ echo $TZ
CET0
$ date
Tue Apr 16 13:49:39 UTC 2013

Whats going on? How to set the timezone on AIX correctly?

Solution

Does your AIX install have the smitty package?
Navigate through the menus:
System Environments -> Change/Show Date and Time -> Change Time Zone Using System Defined Values
Find whatever timezone is closest to you. I'm in America/New_York

Comments

[Admin]

CET == Central European Time, CEST == Central European Savings Time during the (approximately) "not winter" months... Not sure what CET0 is...

[0xC0000022L]

@twalberg: surprisingly it's called Central European Summer Time, even though the S in DST means Saving :)

[Lorinczy Zsigmond]

Best option: TZ=Europe/YourCapital if it doesn't work (old AIX, incomplete timezone-database): TZ=CET-1CEST-2,M3.5.0/2,M10.5.0/3. Nonetheless, you can 'deactivate' DST, if you set TZ=CET-1CET-1