neelesh_gurjar

Scenario:

Linux machine with/home having ext3 type of filesystem.
You have welcome.jpg file in /home/test. And you have deleted it by "rm -f " command.
Now we will recover that welcome.jpg

Step 1. --> Check which Filesystem /home is.


So we got Filesystem no - /dev/sda3


Step 2. -->  Debugfs to get necessary information

The debugfs program is an interactive file system debugger that is installed by default with most common Linux distributions. This program is used to manually examine and change the state of a filesystem. In our situation, we're going to use this program to determine the inode which stored information about the deleted file and to what block group the deleted file belonged.

I was getting below error in samba log for accessing Samba from Windows 98

ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user

Solution --> In smb.conf insert following lines under global section.

ntlm auth = Yes
client ntlmv2 auth = Yes

And restart samba.

1. Create autologin.c and put following code in it.

int main()
{
execlp( "login", "login", "-f", "andrew", 0);
}

2. Compile it with following command:

cc autologin.c -o autologin

3. Do following changes in /etc/inittab
Please add "-n -l /usr/sbin/autologin" immidiate after "/sbin/getty"
Your line will be like this:

c1:12345:respawn:/sbin/agetty -n -l /usr/sbin/autologin 38400 tty1 linux


4. Reboot

In linux users home folders are in /home. Many times we need it in /var/www/html but we do not want to change default setting. Then there is a simple workaround for this.

Step 1. : Just create directory home under /var/www/html
Step 2. : mount --bind /home /var/www/html/home
Step 3. : Put above command in init script. For eg. If you are using CentOS then put it in /etc/rc.local

And your link is ready. :)

We will setup 2 domains mydomain1 & mydomain2 on 1 linux machine with samba.

1. Create 2 samba config files in /etc/samba/
     a. smb.conf_mydomain1
     b. smb.conf_mydomain2

2. Your smb.conf_mydomain1 will look like below:

Today When I ask in one department in company that "Can we switch over to Windows? As some body is donating Licensing cost for those PCs" All users said "No, We can't work on Windows now. We need only Linux"...

I got pleasent surprised by their reply. I thought that they will switch to Windows.

Three years back when I was pushing these users to work on Linux. I had to explain them advantages of Linux. They faced lots of issues in their daily work. Some of them I could resolved, In some cases they had to change their working style, some of them took a loing time also. But now when they are using it for last 2 years without any issue, they dont want to go back to Windows. They said that they forgot how to work on Windows. .... They got addicted to Linux now.....

People say that Linux is not user friendly and cannot be used for Desktops for general users.
Now I can surely say, if users, admins, management plans to use Linux, works hard on it without having windows in mind then they can switch to Linux. Offcourse proffessional companies like Adobe, Corel, Font making companies should make applications for Linux also.

1.  echo "blacklist ath5k" >> /etc/modprobe.d/blacklist
2. Download latest madwifi-hal   from http://snapshots.madwifi.org/madwifi-hal-0.10.5.6/
3. Extract the tarball & go to extracted directory and install it with following commands:
  
     install
     modprobe ath_pci
     modprobe ath_hal

4. Create or open a file named  in the /etc/pm/config.d/config
   Add following line:   SUSPEND_MODULES="ath_pci"

5. Reboot it and then configure wireless interface in Yast2.

Sharing Printer for Windows from Linux -->

smb.conf will be =============>

[global]
        dos charset = ASCII
        display charset = UTF-8
        workgroup = WORKGROUP
        netbios name = PRINT
        security = SHARE
        max xmit = 65535
        deadtime = 15
        socket options = IPTOS_LOWDELAY TCP_NODELAY SO_SNDBUF=16384 SO_RCVBUF=16384
        printcap name = cups
        printing = cups
        log file = /var/log/samba/%m.log

[printers]
        comment = All Printers
        path = /var/tmp
        guest ok = Yes
        printable = Yes
        browseable = yes

[print$]
        comment = Printer Drivers
        path = /var/lib/samba/drivers
        guest ok = Yes

[Test]
        comment = Test
        path = /var/lib/samba
        read only = No
        guest ok = Yes
        printable = Yes
        printer name = Test
        use client driver = Yes
        oplocks = No

===========================

/etc/cups/cupsd.conf ===================>


LogLevel debug
SystemGroup sys root
Port 631
Listen /var/run/cups/cups.sock
Browsing Off
DefaultAuthType Basic

<Location />
  Order allow,deny
   Allow from All
</Location>

<Location /admin>
  Order allow,deny
  Allow from All
</Location>

<Location /admin/conf>
  Order allow,deny
   Allow from All
</Location>

Note: If permissions are not proper then you may get "client-error-not-authorized" this error in Samba log.

================================

Please uncomment below line from /etc/cups/mime.convs

application/octet-stream        application/vnd.cups-raw        0       -

Note : If it is commented then you may get "client-error-document-format-not-supported" this error in samba log.

================================

Now restart cups and add printer in Windows.

Good Luck !!! :)

I am using CentOS 5.1 with Wine-0.9.57. While executin Program "Write.exe" with wine I was getting following error:

[neel_g@test drive_c]$ wine write.exe
preloader: Warning: failed to reserve range 00000000-60000000
preloader: Warning: failed to reserve range 00000000-60000000
preloader: Warning: failed to reserve range 00000000-60000000
err:dosmem:setup_dos_mem Cannot use first megabyte for DOS address space, please report
preloader: Warning: failed to reserve range 00000000-60000000
err:dosmem:setup_dos_mem Cannot use first megabyte for DOS address space, please report
err:dosmem:setup_dos_mem Cannot use first megabyte for DOS address space, please report
err:dosmem:load_winedos Could not load winedos.dll, DOS subsystem unavailable
winevdm: unable to exec '--app-name': 16-bit support missing


To resovle this issue:

1.  # cat /proc/sys/vm/mmap_min_add
        65536
2.  I added following line to /etc/sysctl.conf
        vm.mmap_min_addr = 0
3. # wineboot
4. The issue got resolved. The program is working fine.  :-)


       

[root@example root]# netstat -u -s
Udp:
    95043801 packets received
    2059 packets to unknown port received.
    12041 packet receive errors
    81665255 packets sent

[root@exampleroot]# netstat -t -s
Tcp:
    2119 active connections openings
    14472 passive connection openings
    0 failed connection attempts
    10 connection resets received
    1372 connections established
    101805453 segments received
    190009367 segments send out
    18675 segments retransmited
    0 bad segments received.
    31811 resets sent
TcpExt:
    ArpFilter: 0
    4892 TCP sockets finished time wait in fast timer
    774734 delayed acks sent
    3375 delayed acks further delayed because of locked socket
    Quick ack mode was activated 58 times
    2792 packets directly queued to recvmsg prequeue.
    1662 packets directly received from backlog
    681773 packets directly received from prequeue
    6711642 packets header predicted
    2594 packets header predicted and directly queued to user
    TCPPureAcks: 87512391
    TCPHPAcks: 8652457
    TCPRenoRecovery: 0
    TCPSackRecovery: 9225
    TCPSACKReneging: 0
    TCPFACKReorder: 0
    TCPSACKReorder: 0
    TCPRenoReorder: 0
    TCPTSReorder: 0
    TCPFullUndo: 0
    TCPPartialUndo: 0
    TCPDSACKUndo: 0
    TCPLossUndo: 2
    TCPLoss: 1069
    TCPLostRetransmit: 0
    TCPRenoFailures: 0
    TCPSackFailures: 817
    TCPLossFailures: 1
    TCPFastRetrans: 9691
    TCPForwardRetrans: 52
    TCPSlowStartRetrans: 122
    TCPTimeouts: 6017
    TCPRenoRecoveryFail: 0
    TCPSackRecoveryFail: 24
    TCPSchedulerFailed: 0
    TCPRcvCollapsed: 0
    TCPDSACKOldSent: 61
    TCPDSACKOfoSent: 0
    TCPDSACKRecv: 2
    TCPDSACKOfoRecv: 0
    TCPAbortOnSyn: 0
    TCPAbortOnData: 17
    TCPAbortOnClose: 1
    TCPAbortOnMemory: 0
    TCPAbortOnTimeout: 256
    TCPAbortOnLinger: 0
    TCPAbortFailed: 0

I have setup Oracle7.3 on SCO Openserver 5.0.

While starting Oracle I was getting error "ORA:01110 File 30 needs media recovery.

I resolved this by following way:

1. Logged in as oracle user.
2. Gave below commands:


# svrmgrl
SVRMGR>connect internal

SVRMGR>startup
THen it gave same error. So DB got mounted but not opened.

SVRMGR>RECOVER

Media Recovery Done.

THen I restarted Oracle and it worked. This time it didnt show the error.
This means it recovered data from "redo.log". I was lucky.

Cheers

Login as Oracle user
# emctl start dbconsole

While Installing Oracle I got following Error:


[oracle@neelesh ORACLE]$ ./runInstaller
Starting Oracle Universal Installer...

Checking installer requirements...

Checking operating system version: must be redhat-3, SuSE-9, redhat-4, UnitedLinux-1.0, asianux-1 or asianux-2
Passed


All installer requirements met.

Preparing to launch Oracle Universal Installer from /tmp/OraInstall2008-07-06_12-26-00PM. Please wait ...[oracle@neelesh ORACLE]$ No protocol specified
Exception in thread "main" java.lang.InternalError: Can't connect to X11 window server using ':0' as the value of the DISPLAY variable.
at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)
at sun.awt.X11GraphicsEnvironment.<clinit>(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at java.awt.GraphicsEnvironment.getLocalGraphicsEnvir onment(Unknown Source)
at java.awt.Window.init(Unknown Source)
at java.awt.Window.<init>(Unknown Source)
at java.awt.Frame.<init>(Unknown Source)
at oracle.ewt.popup.PopupFrame.<init>(Unknown Source)
at oracle.ewt.lwAWT.BufferedFrame.<init>(Unknown Source)
at oracle.sysman.oio.oioc.OiocOneClickInstaller.<init >(OiocOneClickInstaller.java:378)
at oracle.sysman.oio.oioc.OiocOneClickInstaller.main( OiocOneClickInstaller.java:2091)


SOLUTION: --

1. login as root
2. # xhost +
3. Login as oracle
4. # xhost +

Now try ./runInstaller.

Give below commands as root user:

mkdir /<different filesys>/tmp
chown root.root /<different filesys>/tmp
chmod 1777 /<different filesys>/tmp
export TEMP=/<different filesys>        
export TMPDIR=/<different filesys>

For removing added "tmpspace" give below commands as root user:

rmdir /<different filesys>/tmp
unset TEMP
unset TMPDIR