generate reasonable passwords at the commmand line


cat /dev/urandom| tr -dc 'a-zA-Z0-9-_!@#$%^&*()_+{}|:<>?='|fold -w 12| head -n 4| grep -i '[!@#$%^&*()_+{}|:<>?=]'


generate strong random passwords at the command line


cat /dev/urandom| tr -dc 'a-zA-Z0-9-_!@#$%^&*()_+{}|:<>?='|fold -w 12| head -n 4| grep -i '[!@#$%^&*()_+{}|:<>?=]'


remove serverbeach backdoor

when you lease a server from ServerBeach, they install a backdoor on your server. Here's how to remove it when you choose CentOS or similar redhat type system.

service sbadm stop
chkconfig --del sbadm
rm -f /etc/ssh/.sbadm_config
rm -f /usr/sbin/sbadm
rm -rf /usr/local/webmin-*
rm -f /etc/init.d/sbadm

perl modules

http://www.cpan.org/modules/by-module/

linux boot disk fun

note to self. never, ever, ever ...leave the custom linux boot disk you made, with the fancy all-in-one kickstart file, in the cd drive of your laptop and reboot.

do not allow it to persist in your cd drive, for even the most trivial length of time for which it is unnecessary...REMOVE IT.

make a bootable custom rhel install disk

run from the root of where you have copied the RHEL disk to and your ks.cfg resides.

# mkisofs -o /root/x/rhel43_app.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -R -J -V -T ./

grantaccess.sh

#!/bin/sh

if [ $# -lt 4 ]; then
echo "syntax: $0 host user time 'reason'"
echo "e.g. grantaccess.sh '0am jan 10' 'reason why'"
exit 1
fi

ssh $1 usermod -U $2
ssh $1 chage -E -1 $2
echo "ssh $1 usermod -L $2 " | at $3
echo "ssh $1 skill -KILL -u $2" | at $3
echo `logname` granted $2 access on $1 till $3 - Reason Given:"$4" | mail -s "Access granted"

BlackBerry Bold "Caller ID" doesnt work

ok, lets be clear...its not the ANI data that's messed up (aka Caller ID) but its the a security feature of the phone that's keeping the name of the contact resolving on the screen when the phone is locked (also not a default setting of the phone).....which in the case of losing your phone is a great thing. In the case of normal usage, its impractical. My phone locks rather quickly and has a message that helps the finder return it if I lose it.

This thread was difficult to find but outlines the situation. however, the steps given in the thread are a little different for the newest version from AT&T. By default, many of the features in 'Options | Security Options | Encryption' are turned off. I went in there and turned a bunch of stuff on....thinking "Hey, Cool! Security is so great...lets turn it on! Oh, wow...it doesnt work anymore. hmm."

To make the Contact Name show up when the phone is locked and ringing, be sure that the 'Include Contacts' for 'Encryption: Device Memory' is 'No'.

The Bold must do some housekeeping when it locks, memory wiping and so forth. The Contact list is potentially a list containing PII, and its probably a requirement somewhere to make sure that data is at rest when the device is idle. Just guessing here...

list APC properties

php -i | grep apc

import dshield block list for pf

/usr/local/bin/wget -q -O - http://feeds.dshield.org/block.txt | egrep -v '#|Start' | awk '{print $1 "/24"}' | sed -n '4,50p;50p' > /etc/pf.blocklist.dshield && pfctl -f /etc/pf.conf

make bootable usb with openbsd 4.6 installer

# fdisk -iy sd0
# disklabel -E sd0
> d *
> a a
##make install partition 1G
> q
# newfs sd0a
# mkdir /mnt/usb
# cd /mnt/usb
# mount /dev/sd0a /mnt/usb
# ftp ftp.openbsd.org
user: anonymous
password: 123456
ftp> cd pub/OpenBSD/4.6/i386
ftp> mget *
mget INSTALL.i386? a
ftp> exit
# cp /boot /mnt/usb/boot
# /usr/mdec/installboot -v /mnt/usb/boot /usr/mdec/biosboot sd0c
# cp /mnt/usb/bsd /mnt/usb/bsd.old
# cp /mnt/usb/bsd.rd /mnt/usb/bsd
# cd /
# umount /mnt/usb
try it


see also: http://bsdanywhere.org/
see also: https://calomel.org/bootable_openbsd_cd.html

allow tftp under selinux

For RHEL5:

# audit2allow -a -M mytftp
# semodule -i mytftp.pp
# service xinetd restart

add virtual hard disk to linux

#in vmware workstation | vm settings
add virtual hard disk to vm

#in vm
fdisk /dev/sdb
n
[ENTER][ENTER]
w
mkfs -t ext3 /dev/sdb1
mkdir /newdir
mount -t ext3 /dev/sdb1 /newdir
echo "/dev/sdb1 /software ext3 defaults 1 1" >> /etc/fstab

See: http://www.matttopper.com/?p=25

remount /

mount -n -o remount /

tw_cli: 3ware controller commands

when replacing a failed disk, you must issue a 'maint deleteunit command', as the 'maint remove' command doesnt do what you might think it does. so, pull the drive, insert the new one, issue a rescan commmand, then deleteunit, then rebuild.

the following commands were used to start rebuiding the raid-1 array on a server with a single 8006 controller.

show ver
info
info c0
rescan
info c0
maint deleteunit c0 u1
maint rebuild c0 u0 p1

list pecl modules and info

You might have to:
`ln -s /usr/local/apache2/bin/apxs /usr/local/bin/apxs`

Then:
`/usr/local/apache2/php/bin/pecl list`
`/usr/local/apache2/php/bin/pecl install apc`
`vi /usr/local/apache2/php/conf/php.ini`
- add 'extension=apc.so'
`/usr/local/apache2/bin/apachectl_admin restart`

list kernel modules

# modinfo $(cut -d' ' -f1 /proc/modules) | sed '/^dep/s/$/\n/; /^file\|^desc\|^dep/!d'

host firewall for the mac

#!/bin/sh
#fwrules

IPFW='/sbin/ipfw -q'

$IPFW -f flush
$IPFW add 2000 allow ip from any to any via lo*
$IPFW add 2010 deny log ip from 127.0.0.0/8 to any in
$IPFW add 2020 deny log ip from any to 127.0.0.0/8 in
$IPFW add 2030 deny log ip from 224.0.0.0/3 to any in
$IPFW add 2040 deny log tcp from any to 224.0.0.0/3 in
$IPFW add 2050 allow log tcp from any to any out
$IPFW add 2060 allow tcp from any to any established
$IPFW add 12190 deny log tcp from any to any


Then apply it to the firewall

# sudo ipfw list
# chmod 600 ./rules
# sudo ipfw ./rules

pecl install apc

make sure that the apxs directory is in the system path.

resize a mounted lvm-managed disk in linux

I have found many overly-complex and incorrect and/or unnecessary instructions all over the web. So, I made this reference for me, but it may work well for you too. I typically use RHEL4/5 in my data center implementations, so these steps cover lvm managed disk space (which is decent for a simple LAMP stack).

I tend to do the following a lot in vmware products (workstation/esx/esxi).

First, check and note the size of your disks and partitions in your target vm.

[root@host]# df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      5.8G  665M  4.9G  12% /
/dev/sda1              99M  9.1M   85M  10% /boot
none                  506M     0  506M   0% /dev/shm

[root@host]# sfdisk -s
/dev/sda:   8385898
/dev/sda1:    104391
/dev/sda2:   8281507
/dev/dm-0:   6160384
/dev/dm-1:   2031616

Then, go into the settings of your vm (e.g. through the vi client) and either add another virtual hard disk or increase the size of the existing disk. In my case i simply extended the existing virtual disk from 8G to 16G.

Reboot.

Check to see that the size of /dev/sda has increased.

[root@host]# sfdisk -s
/dev/sda:  16777216
/dev/sda1:    104391
/dev/sda2:   8281507
/dev/dm-0:   6160384
/dev/dm-1:   2031616

[root@host]# sfdisk -l

Disk /dev/sda: 2088 cylinders, 255 heads, 63 sectors/track
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start     End   #cyls    #blocks   Id  System
/dev/sda1   *      0+     12      13-    104391   83  Linux
/dev/sda2         13    1043    1031    8281507+  8e  Linux LVM
/dev/sda3          0       -       0          0    0  Empty
/dev/sda4          0       -       0          0    0  Empty

/* If you increased the size of your existing disk, its probably easiest to boot from the gparted-live disk and create a new primary partition in the newly free space, format ext3. */
wget http://downloads.sourceforge.net/project/gparted/gparted-live-stable/0.4.6-1/gparted-live-0.4.6-1.iso?use_mirror=softlayer

reboot

/* check for /dev/sda3, your new parition */

[root@host]# sfdisk -s
/dev/sda:  16777216
/dev/sda1:    104391
/dev/sda2:   8281507
/dev/sda3:   8385930
/dev/dm-0:   6160384
/dev/dm-1:   2031616

/* create the lvm pv reference */

[root@host]# pvcreate /dev/sda3

/* extend the lvm vg reference */

[root@host]# vgextend VolGroup00 /dev/sda3

/* note the free space for your upcoming `lvextend` command */

[root@host]# vgdisplay

  --- Volume group ---
  VG Name               VolGroup00
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  4
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               15.84 GB
  PE Size               32.00 MB
  Total PE              507
  Alloc PE / Size       250 / 7.81 GB
  Free  PE / Size       257 / 8.03 GB
  VG UUID               L7woQB-ymCv-NeWL-i47M-b5Ua-fOHQ-hM0DXI

/* extend the lvm vg reference */

[root@host]# lvextend -L+8.03G /dev/VolGroup00/LogVol00

/* resize the volume group while its still mounted */

[root@host]# ext2online /dev/VolGroup00/LogVol00

check the following

[root@host]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       14G  668M   13G   6% /
/dev/sda1              99M  9.1M   85M  10% /boot
none                  506M     0  506M   0% /dev/shm

[root@host]# sfdisk -l

Disk /dev/sda: 2088 cylinders, 255 heads, 63 sectors/track
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start     End   #cyls    #blocks   Id  System
/dev/sda1   *      0+     12      13-    104391   83  Linux
/dev/sda2         13    1043    1031    8281507+  8e  Linux LVM
/dev/sda3       1044    2087    1044    8385930   83  Linux
/dev/sda4          0       -       0          0    0  Empty

now, go on with your life.