When troubleshooting apache server it is always a first step to check on the logs. If your apache server won’t start check /var/log/messages or /var/log/httpd/error_log and inspect properly what is the messages. If you are getting this kind of messages.

[emerg] (28)No space left on device: Couldn’t create accept lock
[notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[notice] Digest: generating secret for digest authentication …
[notice] Digest: done

First off, check to make sure that you really aren’t out of disk space, or have hit a quota limit. Another way that Apache can create the “accept lock” is with a semaphore. A semaphore is an inter-process communication tool that is used by Apache to communicate with it’s child processes. This error message may mean that Apache couldn’t create a new semaphore.

You can type df -h to check if you ran out of disk space.

Check to see how many semaphores are currently in use. If Apache is running correctly, you should see something like this:

# ipcs -s
------ Semaphore Arrays --------
key semid owner perms nsems
0x00000000 68681743 apache 600 1
0x00000000 68714515 apache 600 1
0x00000000 68747291 apache 600 1

If Apache is stopped, and you still see these semaphores, then you can safely kill them by running this command for each semaphore id (in the second column).

$ ipcrm -s <semid>

To destroy all semaphores, you can run this from the command line (with “apache” being the apache-user):

for semid in `ipcs -s | grep apachec | cut -f2 -d" "`
do ipcrm -s $semid
done

If you are out of semaphores

If you can’t create any more semaphores:

Sometimes your system may need to increase the number of semaphores that are available on the system. This requires a change to a kernel parameter. If you are running on a virtual server and cannot modify kernel parameters, you may need to ask your hosting provider to change this parameter on their host server To view the current parameters:

# ipcs -l
------ Shared Memory Limits --------
max number of segments = 4096
max seg size (kbytes) = 32768
max total shared memory (kbytes) = 8388608
min seg size (bytes) = 1

------ Semaphore Limits --------
max number of arrays = 1024
max semaphores per array = 250
max semaphores system wide = 256000
max ops per semop call = 32
semaphore max value = 32767

------ Messages: Limits --------
max queues system wide = 1024
max size of message (bytes) = 8192
default max size of queue (bytes) = 16384

To change these parameters, modify the file /etc/sysctl.conf and add the following lines:

kernel.msgmni = 1024
kernel.sem = 250 256000 32 1024

Then load these settings with the command:

sysctl -p

Your Apache process should now be able to create the needed semaphores and run properly.

Some simple command line utilities you can use on your Windows and Linux computer to test DNS resolution. this will also show you how you can quickly test if you have resolution via a name server or not. Many times this comes up, a DNS server is down; client loses IP connectivity and can”t resolve DNS, DNS cache poisoning. Using this handy tools can guide you quickly to see how you can test to see if your system is ”ok” and resolving names to IPs properly.

1. You have to see if DNS resolution is working you can see if the DNS server you are configured to query.

C:\Documents and Settings\raxso>nslookup www.google.com
Server: everest.local
Address: 192.168.1.200

Non-authoritative answer:
Name: www.l.google.com
Addresses: 72.14.235.99, 72.14.235.147, 72.14.235.104
Aliases: www.google.com

2. When you query my Local DNS I can see that www.google.com has mulitiple IP addresses.

3. Now, you can ping with the -a switch to also verify if DNS resolution is work. Pinging Google’s IP address with the -a switch produces the DNS name of the system.

C:\Documents and Settings\raxso>ping -a 72.14.235.99

Pinging tw-in-f99.google.com [72.14.235.99] with 32 bytes of data:

Reply from 72.14.235.99: bytes=32 time=85ms TTL=245
Reply from 72.14.235.99: bytes=32 time=85ms TTL=245
Reply from 72.14.235.99: bytes=32 time=85ms TTL=245
Reply from 72.14.235.99: bytes=32 time=97ms TTL=245

Ping statistics for 72.14.235.99:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 85ms, Maximum = 97ms, Average = 88ms

Although this is a simple command line but very helpful when you are troubleshooting network connectivity and DNS resolution.

In doing this procedure you should login as administrator of your PC.

1. Right Click My Computer then explore. Look for autorun.inf and Delete this.

2. Click Start - Run and type regedit. Click HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon

3. Look for LegalNoticeCaption and delete the data “PROMISE???”

4. Look for LegalNoticeText and delete the data “I am still waiting for the strawberry coming from my baguio! Pls…Help!”

Then close regedit and restart your computer.

Note: Just remove the the value data. ok

Hope this helps to all of you who have this kind of virus.

Symptoms: C: drive has an [autoplay] function when right-clicked. Internet Explorer has “TAGA LIPA ARE!” in it’s title bar.

Mode of Transfer: USB, Fixed/Portable HDD

Target: Internet Explorer, Registry, MSConfig, Autorun.inf

Effects: Every Mass Storage Device linked to the infected PC will be inserted with an autorun file which will trigger the Windows Scripting Service to run its main file “FS6519.dll.vbs”, which is marked as a system file and is in the root directory of the Drive.

Note: You must have administrator privilege on the computer you are working with to remove this virus.

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