Output from 'groups' is suddently different to /etc/group

[R. Diez]

 >> I found it unfortunate that the installer (Synaptic) did not warn me
 >> that I had to log out and in again. I expected that everything would
 >> work straight away, but my user account was not immediately a member
 >> of those groups. I guess that this is a limitation of the underlying
 >> Debian APT system.

 > I've never used a Unix (and I've used quite a few) where you
 > could modify groups and the changes would apply without
 > logging out and back in.

Yes, but how would I know that the package I just installed has changed 
group membership? Or should I assume the worst and restart my system 
after installing every package, like on Windows?


 > I'm not sure what your actual problem is. Are you saying that
 > the above situation persists even after logging out and
 > back in, or even after e.g. a reboot?

Yes. I have rebooted a few times in the meantime, and the problem is 
still there.


 > If so, posting your passwd and group files (sanitised please!)
 > might reveal the problem.

I am not sure what I should sanitise, so I'm hoping that posting them 
unmodified is OK:


---- /etc/passwd ----

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin
gnats:x:41:41:Gnats Bug-Reporting System 
(admin):/var/lib/gnats:/usr/sbin/nologin
nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
syslog:x:101:104::/home/syslog:/bin/false
messagebus:x:102:106::/var/run/dbus:/bin/false
usbmux:x:103:46:usbmux daemon:/home/usbmux:/bin/false
dnsmasq:x:104:65534:dnsmasq:/var/lib/misc:/bin/false
avahi-autoipd:x:105:113:Avahi autoip 
daemon:/var/lib/avahi-autoipd:/bin/false
kernoops:x:106:65534:Kernel Oops Tracking Daemon:/:/bin/false
rtkit:x:107:114:RealtimeKit:/proc:/bin/false
saned:x:108:115::/var/lib/saned:/bin/false
whoopsie:x:109:116::/nonexistent:/bin/false
avahi:x:110:117:Avahi mDNS daemon:/var/run/avahi-daemon:/bin/false
lightdm:x:111:118:Light Display Manager:/var/lib/lightdm:/bin/false
colord:x:112:121:colord colour management daemon:/var/lib/colord:/bin/false
hplip:x:113:7:HPLIP system user:/var/run/hplip:/bin/false
pulse:x:114:122:PulseAudio daemon:/var/run/pulse:/bin/false
rdiez:x:1000:1000:rdiez:/home/rdiez:/bin/bash
postfix:x:115:125::/var/spool/postfix:/bin/false
sshd:x:116:65534::/var/run/sshd:/usr/sbin/nologin
dictd:x:117:127:Dictd Server:/var/lib/dictd:/bin/false
debian-spamd:x:118:128::/var/lib/spamassassin:/bin/sh
davfs2:x:119:131::/var/cache/davfs2:/bin/false
ntp:x:120:132::/home/ntp:/bin/false
timidity:x:122:135:TiMidity++ MIDI sequencer 
service:/etc/timidity:/bin/false
zeroinst:x:121:134::/home/zeroinst:/bin/false
systemd-timesync:x:123:137:systemd Time 
Synchronization:/run/systemd:/bin/false
systemd-network:x:124:138:systemd Network 
Management:/run/systemd/netif:/bin/false
systemd-resolve:x:125:139:systemd Resolver:/run/systemd/resolve:/bin/false
systemd-bus-proxy:x:126:140:systemd Bus Proxy:/run/systemd:/bin/false
uuidd:x:100:101::/run/uuidd:/bin/false
_apt:x:127:65534::/nonexistent:/bin/false
sddm:x:128:142:Simple Desktop Display Manager:/var/lib/sddm:/bin/false
speech-dispatcher:x:129:29:Speech 
Dispatcher:/var/run/speech-dispatcher:/bin/false
dhcpd:x:130:143::/var/run:/bin/false
roundup:x:999:999::/var/lib/roundup:
geoclue:x:131:144::/var/lib/geoclue:/bin/false
libvirt-qemu:x:64055:146:Libvirt Qemu:/var/lib/libvirt:/bin/false
libvirt-dnsmasq:x:132:145:Libvirt 
Dnsmasq:/var/lib/libvirt/dnsmasq:/bin/false


---- /etc/group ----

root:x:0:
daemon:x:1:
bin:x:2:
sys:x:3:
adm:x:4:syslog,rdiez
tty:x:5:rdiez
disk:x:6:
lp:x:7:
mail:x:8:
news:x:9:
uucp:x:10:
man:x:12:
proxy:x:13:
kmem:x:15:
dialout:x:20:rdiez
fax:x:21:
voice:x:22:
cdrom:x:24:rdiez
floppy:x:25:
tape:x:26:
sudo:x:27:rdiez
audio:x:29:pulse,timidity
dip:x:30:rdiez
www-data:x:33:
backup:x:34:
operator:x:37:
list:x:38:
irc:x:39:
src:x:40:
gnats:x:41:
shadow:x:42:
utmp:x:43:
video:x:44:
sasl:x:45:
plugdev:x:46:rdiez
staff:x:50:
games:x:60:
users:x:100:
nogroup:x:65534:
netdev:x:102:
crontab:x:103:
syslog:x:104:
fuse:x:105:rdiez
messagebus:x:106:
ssl-cert:x:107:
lpadmin:x:108:rdiez
scanner:x:109:saned
mlocate:x:110:
ssh:x:111:
utempter:x:112:
avahi-autoipd:x:113:
rtkit:x:114:
saned:x:115:
whoopsie:x:116:
avahi:x:117:
lightdm:x:118:
nopasswdlogin:x:119:
bluetooth:x:120:
colord:x:121:
pulse:x:122:
pulse-access:x:123:
rdiez:x:1000:
sambashare:x:124:rdiez
postfix:x:125:
postdrop:x:126:
dictd:x:127:
debian-spamd:x:128:
wireshark:x:129:rdiez
winbindd_priv:x:130:
davfs2:x:131:
ntp:x:132:
vboxusers:x:133:
timidity:x:135:
zeroinst:x:134:
systemd-journal:x:136:rdiez
systemd-timesync:x:137:
systemd-network:x:138:
systemd-resolve:x:139:
systemd-bus-proxy:x:140:
uuidd:x:101:
input:x:141:
sddm:x:142:
dhcpd:x:143:
roundup:x:999:
geoclue:x:144:
libvirtd:x:145:rdiez
kvm:x:146:


I would like to know who is setting up the group membership when logging 
in, so that I can try to debug the problem there. "su - $USER" obviously 
does it differently. I would have expected that the 
method/library/whatever is shared (the same in both scenarios).

I found no complaint about logon or group problems in the usual syslog 
oder dmesg.

Thanks in advance,
   rdiez