I am using Fedora 17 and over the last few days I am having an issue with my system. Whenever I try to start httpd it shows me:Error: No space left on deviceWhen I execute systemctl status httpd.service, I receive the following output:httpd.service - The Apache HTTP Server (prefork MPM)          Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled)          Active: inactive (dead) since Tue, 19 Feb 2013 11:18:57 +0530; 2s ago         Process: 4563 ExecStart=/usr/sbin/httpd $OPTIONS -k start (code=exited, status=0/SUCCESS)          CGroup: name=systemd:/system/httpd.serviceI tried to Google this error and all links point to clearing the semaphores. I don't think this is the issue as I tried to clear the semaphores but that didn't work.Edit 1here is the output of df -g[root@localhost ~]# df -hFilesystem              Size  Used Avail Use% Mounted onrootfs                   50G   16G   32G  34% /devtmpfs                910M     0  910M   0% /devtmpfs                   920M  136K  920M   1% /dev/shmtmpfs                   920M  1.2M  919M   1% /run/dev/mapper/vg-lv_root   50G   16G   32G  34% /tmpfs                   920M     0  920M   0% /sys/fs/cgrouptmpfs                   920M     0  920M   0% /media/dev/sda1               497M   59M  424M  13% /boot/dev/mapper/vg-lv_home  412G  6.3G  385G   2% /homeHere is the deatail of httpd error log[root@localhost ~]# tail -f /var/log/httpd/error_log[Tue Feb 19 11:45:53 2013] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)[Tue Feb 19 11:45:53 2013] [notice] Digest: generating secret for digest authentication ...[Tue Feb 19 11:45:53 2013] [notice] Digest: done[Tue Feb 19 11:45:54 2013] [notice] Apache/2.2.23 (Unix) DAV/2 PHP/5.4.11 configured -- resuming normal operations[Tue Feb 19 11:47:23 2013] [notice] caught SIGTERM, shutting down[Tue Feb 19 11:48:00 2013] [notice] SELinux policy enabled; httpd running as context system_u:system_r:httpd_t:s0[Tue Feb 19 11:48:00 2013] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)[Tue Feb 19 11:48:00 2013] [notice] Digest: generating secret for digest authentication ...[Tue Feb 19 11:48:00 2013] [notice] Digest: done[Tue Feb 19 11:48:00 2013] [notice] Apache/2.2.23 (Unix) DAV/2 PHP/5.4.11 configured -- resuming normal operationstail: inotify resources exhaustedtail: inotify cannot be used, reverting to pollingEdit 2here is the output of df-i[root@localhost ~]# df -iFilesystem               Inodes  IUsed    IFree IUse% Mounted onrootfs                  3276800 337174  2939626   11% /devtmpfs                 232864    406   232458    1% /devtmpfs                    235306      3   235303    1% /dev/shmtmpfs                    235306    438   234868    1% /run/dev/mapper/vg-lv_root  3276800 337174  2939626   11% /tmpfs                    235306     12   235294    1% /sys/fs/cgrouptmpfs                    235306      1   235305    1% /media/dev/sda1                128016    339   127677    1% /boot/dev/mapper/vg-lv_home 26984448    216 26984232    1% /homeThanks
Httpd : no space left on device
linux;fedora;limit;inotify;apache httpd
Here we see evidence of a problem:tail: inotify resources exhaustedBy default, Linux only allocates 8192 watches for inotify, which is ridiculously low. And when it runs out, the error is also No space left on device, which may be confusing if you aren't explicitly looking for this issue.Raise this value with the appropriate sysctl:fs.inotify.max_user_watches = 262144(Add this to /etc/sysctl.conf and then run sysctl -p.)