Miscellaneous Answers

• wmic errors

  [wmi/wmic.c:212:main()] ERROR: Retrieve result data.
  NTSTATUS: NT code 0x80041010 - NT code 0x80041010
  
  caused by a typo in from Win32_....
  

  Nice list of other error codes: http://www.iggyt.org/doku.php?id=wiki:infrastructure_tools:wmi:wmi-wmic
  
  
• strace httpd Sometimes Apache seems to be slow for one web site but not others (in my case it was trying to connect to a disappearing web site)

     ps -ef | grep httpd | grep -v grep \
          gawk '{print " -p $2 }'  | xargs strace  -tt -o /tmp/httpdStrac.$$
  

  I then grep/gawk and sort out the pids for the stalled httpd.
  
  
  
• Came across this error when some users couldn't connect to our Solaris 10 vsftp daemon, this error was showing up in /var/adm/messages, but others were connected just fine.

  Jul 21 11:20:43 ftpserver vsftpd[8032]: [ID 140027 daemon.error] warning: can't verify hostname: gethostbyname(8-221.int.cec.wustl.edu) failed
  Jul 21 11:20:43 ftpserver vsftpd[8032]: [ID 913506 daemon.warning] refused connect from 172.16.8.221 (name/address mismatch)
  
  

  This turned out to be caused by tcp_wrappers, you have to disable it.

   inetadm -m  svc:/network/ftp:default tcp_wrappers=FALSE
  

• Client MAC running OS X Leopard:

  Server: smbd 3.4.2 with kerberos for AD 2008 1.6.1-31 pam_krb5 2.2.14-10
  Error: [2009/10/15 10:19:17, 0] lib/util_sock.c:1685(get_peer_name)
      Matchname failed on xxx.wustl.edu ::fff:172.x.x.x
  
  Turned off ipv6 on the MAC
  
  

• firefox 3.5.3 (32 bit) and 3.5.5 running on 64 bit centos 5.3i

  Just plain crashes, turns out making a secure (https) connection is the problem.
  using strace, post starting firefox, the following libraries could not be found: libcurl.so.3, libcurl-gnutls.so.3, libssl.so.0.9.7, libcrypto.so.0.9.7
  for me they were all in /opt/Adobe/Reader8/Reader/intellinux/lib
  
  So make links (ln -s) to them in your firefox install directory.
  
  cd .../firefox32-3.5.3
  ln -s /opt/Adobe/Reader8/Reader/intellinux/lib/libcurl.so.3
  ln -s /opt/Adobe/Reader8/Reader/intellinux/lib/libcurl.so.3.0.0 libcurl-gnutls.so.3
  ln -s /opt/Adobe/Reader8/Reader/intellinux/lib/libssl.so.0.9.7
  ln -s /opt/Adobe/Reader8/Reader/intellinux/lib/libcrypto.so.0.9.7
  
  

• copy cd/dvd to iso to use on machine with out cd/dvd drive

  
  umout if it is mounted
  dd if=/dev/dvd of=somedvd.iso
  scp somedvd.iso somehost:
  mkdir /mnt/iso
  somehost# mount -o loop somedvd.iso /mnt/iso
  

• make a CentOS boot usb-stick for netinstall

  
  1) lftp or wget to your favorite iso site and get .../centos/5.5/os/x86_64/images/diskboot.img
  2) dd if=diskboot.img of=/dev/sdc
  3) take the usb-stick and boot it, you will need the above host and path to do the reset of the install it when ask for host and path, give it everything upto but exclude images/diskboot.img
  
  

• apache on linux, mod_qos error mutex nospace left on device

  
  try: ipcs -s | grep root | awk ' { print $2 } ' | xargs -n 1 ipcrm -s
  (thanks Mark)

• Build OpenCV on CentOS

  -fPIC error in make at end

  
  1) if you plan on using python (2.6 in our case) with OpenCV, you need to run ./configure with --enable-shared , then build python. Don't forget to create /etc/ld.so.conf.d/python.so.conf. ; ldconfig
  2) you will need cmake (yum install)

• So the machine only crashes under load?

  MEMTEST86+ runs for over a whole weekend, no problems.
  breakin from advanced clustering runs for a whole weekend with out problems.
  Try matlab or octave, s=sqrt(ram-in-bytes/16) ; tic;m=rand(s,s); mm=m*m; toc
  It will use all of memory and gets every cpu/core running!

• building 64bit php5 with mysql, on centos 5

  ./configure --prefix=/usr/local/php52 --with-pdo-mysql --with-mysql
  gives:
  checking for mysql_errno in -lmysqlclient... no
  configure: error: Try adding --with-zlib-dir=<DIR>. Please check config.log for more information.
  
  adding with-zlib doesn't help, logs show it trying to use 32 bit version, so:
  ./configure --prefix=/usr/local/php52 --with-pdo-mysql --with-mysql --with-libdir=/usr/lib64
  gives:
  configure: error: Cannot find libmysqlclient under /usr.
  Note that the MySQL client library is not bundled anymore!
  
  strange error given the correct incantation is:
  ./configure --prefix=/usr/local/php52 --with-pdo-mysql --with-mysql --libdir=/usr/lib64 --with-libdir=lib64
  :)

• #ffff##: in .Xauthority is not good

  the simple thing is to just remove the .Xauthority file.