Limiter les logs

Comme vous le savez, le raspberry tourne sur une SDcard, et cette mémoire flash n’aime pas trop les écritures à outrance.

Je vais donc essayer de trouver des solutions pour limiter les logs qui ne sont pas importants.

# find -mtime -1 -type f -exec ls -l {} \;
-rw-r--r-- 1 root root 86111 juil.  2 21:41 ./samba/log.smbd
-rw-r--r-- 1 root root 1829 juil.  1 21:49 ./samba/log.nmbd
-rw-r----- 1 root adm 1552222 juil.  2 21:17 ./auth.log
-rw-r----- 1 root adm 563699 juil.  2 19:24 ./messages
-rw-r----- 1 root adm 5876077 juil.  2 21:48 ./syslog
-rw-r----- 1 root adm 12252 juil.  2 19:24 ./user.log
-rw-rw-r-- 1 root utmp 2688 juil.  2 07:22 ./wtmp
-rw-r--r-- 1 root root 2408 juil.  2 19:24 ./rsnapshot.log
-rw-r----- 1 root adm 6718716 juil.  2 19:24 ./kern.log
-rw-r----- 1 root adm 1176251 juil.  2 06:25 ./syslog.1
-rw-r--r-- 1 root root 24048 juil.  1 22:05 ./faillog
-rw-rw-r-- 1 root utmp 292584 juil.  2 07:22 ./lastlog
-rw-r--r-- 1 root root 6405 juil.  1 22:12 ./aptitude
-rw-r----- 1 root adm 548236 juil.  2 21:48 ./daemon.log

On va analyser tous les fichiers qui ont été modifié récemment et qui ont une taille élevée.

Extrait :

Jul  3 00:49:15 edmchome kernel: [219188.969066] net_ratelimit: 2423 callbacks suppressed
Jul  3 00:49:15 edmchome kernel: [219188.969107] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.969815] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.969866] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.969968] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970058] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970093] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970121] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970146] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970188] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:15 edmchome kernel: [219188.970215] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.272645] net_ratelimit: 3043 callbacks suppressed
Jul  3 00:49:22 edmchome kernel: [219196.272699] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.273692] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.273777] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.273889] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.273941] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.273967] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.274021] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.274191] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.274233] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:49:22 edmchome kernel: [219196.274259] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219244] net_ratelimit: 3633 callbacks suppressed
Jul  3 00:51:44 edmchome kernel: [219338.219286] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219383] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219516] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219554] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219598] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219664] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219705] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219732] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219754] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
Jul  3 00:51:44 edmchome kernel: [219338.219830] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped

Solution trouvé : http://wood1978.dyndns.org/~wood/wordpress/2013/04/03/fix-smsc95xx-1-1-11-0-eth0-kevent-2-may-have-been-dropped-on-raspberry-pi-with-arch-linux

Ajouter smsc95xx.turbo_mode=N dans le fichier /boot/cmdline.txt

smsc95xx.turbo_mode=N dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=noop rootdelay=24

Modifier ou ajoutez les valeurs suivantes dans le fichier /etc/sysctl.conf

#vm.vfs_cache_pressure = 100
vm.vfs_cache_pressure = 300
#vm.min_free_kbytes=8192
vm.min_free_kbytes=32768

Mettez à jour sysctl

sysctl -p