Monthly Archives: October 2012

Symantec Endpoint Protection - How to cleanup excessive disk usage

Publicat la 30 October 2012 No comments

This document describes the necessary steps required to clean up the content of the folder C:\Program Files\Symantec\Symantec Endpoint Protection Manager\Inetpub\content\

1. Stop the Service Endpoint Protection services
[codesyntax lang="bash"]

start -> run -> services.msc

[/codesyntax]

Symantec Embedded Database
Symantec Endpoint Protection
Symantec Endpoint Protection Manager
Symantec Event Manager
Symantec Management Client
Symantec Settings Manager

2. Navigate to the folder C:\Program Files\Symantec\Symantec Endpoint Protection Manager\Inetpub\content\ and then from each of the folders present under the CONTENT folder, go in and delete ALL the sub-folders with names in DIGITS.

3. At the END of the file C:\Program Files\Symantec\Symantec Endpoint Protection Manager\tomcat\etc\conf.properties add:
scm.lucontentcleanup.threshold=x (preferably between 1 to 5, since 10 is the default value).

4. Start all services stopped at the step 1.

How to install a PPTP server on debian squeeze

Publicat la 26 October 2012 No comments

This document describes the required steps to make a fully functional PPTP server on debian squeeze and how to configure Arno iptables firewall to accept incoming connections to PPTP server (in case you use this great firewall script).

If you don't use Arno iptables firewall but you still want to share internet connection with PPTP server please view the last note.

PPTP or PopTop is a vpn implementation that is rather similar to OpenVPN. The difference is that PPTP is quite a bit less secure than OpenVPN, as it is not encrypted. That said, if you need quick VPN solution that’s easy and hassle free to set up, PPTP is the obvious choice.

1. Install the PPTP server package.

[codesyntax lang="bash"]

apt-get install pptpd

[/codesyntax]

2. Edit the /etc/pptpd.conf configuration file.

[codesyntax lang="bash"]

echo "localip 192.168.1.1" >> /etc/pptpd.conf
echo "remoteip 192.168.1.236-239" >> /etc/pptpd.conf

[/codesyntax]

The Local IP is the IP address of the server, remoteip specifies the IPs the vpn will assign its clients.

3. Edit the /etc/ppp/pptpd-options configuration file:

name Private.VPN
refuse-pap
refuse-chap
refuse-mschap
require-mschap-v2
require-mppe-128
ms-dns 8.8.8.8
proxyarp
nodefaultroute
lock
nobsdcomp
noipx
mtu 1490
mru 1490

4. Edit the chap secrets file /etc/ppp/chap-secrets and add to it the authentication credentials for a user’s connection, in the following syntax:

username <TAB> * <TAB> users-password <TAB> *

5. Restart the connection’s daemon for the settings to take affect:

[codesyntax lang="bash"]

/etc/init.d/pptpd restart

[/codesyntax]

6. Enable Forwarding (this is an optional step).

Note: By enabling forwarding we make the entire network available to us when we connect and not just the VPN server itself. Doing so allows the connecting client to "jump" through the VPN server, to all other devices on the network.

Edit the sysctl file:

[codesyntax lang="bash"]

vim /etc/sysctl.conf

[/codesyntax]

Find the net.ipv4.ip_forward line and change the parameter from 0 (disabled) to 1 (enabled):

net.ipv4.ip_forward=1

6. You can either restart the system or issue this command for the setting to take affect:

[codesyntax lang="bash"]

sysctl -p

[/codesyntax]

7. Configure Arno iptables firewall script

[codesyntax lang="bash"]

vim /etc/arno-iptables-firewall/debconf.cfg

[/codesyntax]

DC_EXT_IF="eth0"

DC_EXT_IF_DHCP_IP=1
DC_OPEN_TCP="1723"
DC_OPEN_UDP=""
DC_INT_IF="ppp+"
DC_NAT=0
DC_INTERNAL_NET="192.168.1.236/30"
DC_NAT_INTERNAL_NET=""
DC_OPEN_ICMP=0

[codesyntax lang="bash"]

vim /etc/arno-iptables-firewall/custom-rules

[/codesyntax]

/sbin/iptables --table nat -A POSTROUTING -o eth0 -j MASQUERADE

8. Restart Arno iptables firewall script:

[codesyntax lang="bash"]

/etc/init.d/arno-iptables-firewall restart

[/codesyntax]

Note:

If you don't use Arno iptables firewall but you still want to share internet connection with PPTP server we have to configure NAT for PPTP connections, otherwise you cannot reach anywhere from this server. Add the following lines at the end of the /etc/rc.local right before exit 0

iptables -P FORWARD ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

Execute the /etc/rc.local file:

[codesyntax lang="bash"]

/etc/rc.local

[/codesyntax]

How to migrate a single disk Linux System to software RAID1

Publicat la 23 October 2012 19 comentarii

This guide explains how to set up software RAID1 on an already running Linux (Ubuntu 12.10) system. The GRUB2 bootloader will be configured in such a way that the system will still be able to boot if one of the hard drives fails (no matter which one).

Preliminary Note

In this tutorial I am using an Ubuntu 12.10 system with two disks, /dev/sda and /dev/sdb which are identical in size.
/dev/sdb is currently unused, and /dev/sda has the following partition:

/dev/sda1: / partition, ext4;
/dev/sda5: swap

After completing this guide I will have the following situation:
/dev/md0: / partition, ext4;
/dev/md1: swap

The current situation:

[codesyntax lang="bash"]

df -h

[/codesyntax]

root@ubuntu:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda1        19G  969M   17G   6% /
udev            494M  4.0K  494M   1% /dev
tmpfs           201M  272K  201M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            502M     0  502M   0% /run/shm
none            100M     0  100M   0% /run/user
root@ubuntu:~#

[codesyntax lang="bash"]

fdisk -l

[/codesyntax]

root@ubuntu:~# fdisk -l

Disk /dev/sda: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00059a4b

Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048    39845887    19921920   83  Linux
/dev/sda2        39847934    41940991     1046529    5  Extended
/dev/sda5        39847936    41940991     1046528   82  Linux swap / Solaris

Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/sdb doesn't contain a valid partition table
root@ubuntu:~#

Installing mdadm

First of all install md tools:

[codesyntax lang="bash"]

aptitude install initramfs-tools mdadm

[/codesyntax]

In order to avoid reboot, let's load few kernel modules:

[codesyntax lang="bash"]

modprobe linear
modprobe multipath
modprobe raid0
modprobe raid1
modprobe raid5
modprobe raid6
modprobe raid10

[/codesyntax]

Now:

[codesyntax lang="bash"]

cat /proc/mdstat

[/codesyntax]

root@ubuntu:~# cat /proc/mdstat

Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
unused devices:
root@ubuntu:~#

Preparing the second disk

To create a software RAID1 on a running system, we have to prepare the second disk added to the system (in this case /dev/sdb) for RAID1, then copy the contents from the first disk (/dev/sda) to it, and finally add the first disk to the RAID1 array.

Let's copy the partition table from /dev/sda to /dev/sdb so that the both disks have the exactly same layout:

[codesyntax lang="bash"]

sfdisk -d /dev/sda | sfdisk --force /dev/sdb

[/codesyntax]

root@ubuntu:~# sfdisk -d /dev/sda | sfdisk --force /dev/sdb
Checking that no-one is using this disk right now ...
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
OK

Disk /dev/sdb: 2610 cylinders, 255 heads, 63 sectors/track

sfdisk: ERROR: sector 0 does not have an msdos signature
/dev/sdb: unrecognized partition table type
Old situation:
No partitions found
New situation:
Units = sectors of 512 bytes, counting from 0

Device Boot    Start       End   #sectors  Id  System
/dev/sdb1   *      2048  39845887   39843840  83  Linux
/dev/sdb2      39847934  41940991    2093058   5  Extended
/dev/sdb3             0         -          0   0  Empty
/dev/sdb4             0         -          0   0  Empty
/dev/sdb5      39847936  41940991    2093056  82  Linux swap / Solaris
Warning: partition 1 does not end at a cylinder boundary
Warning: partition 2 does not start at a cylinder boundary
Warning: partition 2 does not end at a cylinder boundary
Warning: partition 5 does not end at a cylinder boundary
Successfully wrote the new partition table

Re-reading the partition table ...

If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes:  dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)
root@ubuntu:~#

And the output of the command:

[codesyntax lang="bash"]

fdisk -l

[/codesyntax]

root@ubuntu:~# fdisk -l

Disk /dev/sda: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00059a4b

Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048    39845887    19921920   83  Linux
/dev/sda2        39847934    41940991     1046529    5  Extended
/dev/sda5        39847936    41940991     1046528   82  Linux swap / Solaris

Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *        2048    39845887    19921920   83  Linux
/dev/sdb2        39847934    41940991     1046529    5  Extended
/dev/sdb5        39847936    41940991     1046528   82  Linux swap / Solaris
root@ubuntu:~#

Change the partitions type on /dev/sdb to Linux raid autodetect:

[codesyntax lang="bash"]

sfdisk --change-id /dev/sdb 1 fd
sfdisk --change-id /dev/sdb 5 fd

[/codesyntax]

root@ubuntu:~# sfdisk --change-id /dev/sdb 1 fd
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
Done

root@ubuntu:~# sfdisk --change-id /dev/sdb 5 fd
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
Done

root@ubuntu:~#

To make sure that there are no remains from previous RAID installations on /dev/sdb, we run the following commands:

[codesyntax lang="bash"]

mdadm --zero-superblock /dev/sdb1
mdadm --zero-superblock /dev/sdb5

[/codesyntax]

If you receive the following error messages then there are no remains from previous RAID installations, which is nothing to worry about:

root@ubuntu:~# mdadm --zero-superblock /dev/sdb1
mdadm: Unrecognised md component device - /dev/sdb1
root@ubuntu:~# mdadm --zero-superblock /dev/sdb5
mdadm: Unrecognised md component device - /dev/sdb5
root@ubuntu:~#

Creating RAID arrays

Now use mdadm to create the raid arrays. We mark the first drive (sda) as "missing" so it doesn't wipe out our existing data:

[codesyntax lang="bash"]

mdadm --create /dev/md0 --level=1 --raid-disks=2 missing /dev/sdb1
mdadm --create /dev/md1 --level=1 --raid-disks=2 missing /dev/sdb5

[/codesyntax]

root@ubuntu:~# mdadm --create /dev/md0 --level=1 --raid-disks=2 missing /dev/sdb1
mdadm: Note: this array has metadata at the start and
may not be suitable as a boot device. If you plan to
store '/boot' on this device please ensure that
your boot-loader understands md/v1.x metadata, or use
--metadata=0.90
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
root@ubuntu:~# mdadm --create /dev/md1 --level=1 --raid-disks=2 missing /dev/sdb5
mdadm: Note: this array has metadata at the start and
may not be suitable as a boot device. If you plan to
store '/boot' on this device please ensure that
your boot-loader understands md/v1.x metadata, or use
--metadata=0.90
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.
root@ubuntu:~#

[codesyntax lang="bash"]

cat /proc/mdstat

[/codesyntax]

root@ubuntu:~# cat /proc/mdstat 
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md1 : active raid1 sdb5[1]
      1045952 blocks super 1.2 [2/1] [_U]
      
md0 : active raid1 sdb1[1]
      19905408 blocks super 1.2 [2/1] [_U]
      
unused devices: <none>
root@ubuntu:~# 

The output above means that we have two degraded arrays ([_U] or [U_] means that an array is degraded while [UU] means that the array is ok).

Create the filesystems on RAID arrays (ext4 on /dev/md0 and swap on /dev/md1)

[codesyntax lang="bash"]

mkfs.ext4 /dev/md0
mkswap /dev/md1

[/codesyntax]

root@ubuntu:~# mkfs.ext4 /dev/md0
mke2fs 1.42.5 (29-Jul-2012)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1245184 inodes, 4976352 blocks
248817 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=0
152 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks: 
    32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 
    4096000

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done   

root@ubuntu:~# mkswap /dev/md1
mkswap: /dev/md1: warning: don't erase bootbits sectors
        on whole disk. Use -f to force.
Setting up swapspace version 1, size = 1045948 KiB
no label, UUID=728f7cfe-bd95-43e5-906d-c8a70023d081
root@ubuntu:~# 

Adjust mdadm configuration file which doesn't contain any information about RAID arrays yet:

[codesyntax lang="bash"]

cp /etc/mdadm/mdadm.conf /etc/mdadm/mdadm.conf_orig
mdadm --examine --scan >> /etc/mdadm/mdadm.conf

[/codesyntax]

Display the content of /etc/mdadm/mdadm.conf:

[codesyntax lang="bash"]

cat /etc/mdadm/mdadm.conf

[/codesyntax]

root@ubuntu:~# cat /etc/mdadm/mdadm.conf
# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#

# by default (built-in), scan all partitions (/proc/partitions) and all
# containers for MD superblocks. alternatively, specify devices to scan, using
# wildcards if desired.
#DEVICE partitions containers

# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes

# automatically tag new arrays as belonging to the local system
HOMEHOST

# instruct the monitoring daemon where to send mail alerts
MAILADDR root

# definitions of existing MD arrays

# This file was auto-generated on Tue, 23 Oct 2012 04:36:40 -0700
# by mkconf $Id$
root@ubuntu:~#

Adjusting The System To RAID1

Let's mount /dev/md0:

[codesyntax lang="bash"]

mkdir /mnt/md0
mount /dev/md0 /mnt/md0

[/codesyntax]

[codesyntax lang="bash"]

mount

[/codesyntax]

root@ubuntu:~# mount
/dev/sda1 on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)
/dev/md0 on /mnt/md0 type ext4 (rw)
root@ubuntu:~# 

Change the UID values in /etc/fstab with the UUID values returned by blkid:

[codesyntax lang="bash"]

blkid /dev/md0 /dev/md1

[/codesyntax]

root@ubuntu:~# blkid /dev/md0 /dev/md1
/dev/md0: UUID="4a49251b-e357-40a4-b13f-13b041c55a9d" TYPE="ext4"
/dev/md1: UUID="728f7cfe-bd95-43e5-906d-c8a70023d081" TYPE="swap"
root@ubuntu:~#

After changing the UUID values the /etc/fstab should look as follows:

[codesyntax lang="bash"]

cat /etc/fstab

[/codesyntax]

root@ubuntu:~# cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# # / was on /dev/sda1 during installation
UUID=4a49251b-e357-40a4-b13f-13b041c55a9d / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=728f7cfe-bd95-43e5-906d-c8a70023d081 none swap sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0
root@ubuntu:~#

Next replace /dev/sda1 with /dev/md0 in /etc/mtab:

[codesyntax lang="bash"]

sed -e "s/dev\/sda1/dev\/md0/" -i /etc/mtab

[/codesyntax]

[codesyntax lang="bash"]

cat /etc/mtab

[/codesyntax]

root@ubuntu:~# cat /etc/mtab
/dev/md0 / ext4 rw,errors=remount-ro 0 0
proc /proc proc rw,noexec,nosuid,nodev 0 0
sysfs /sys sysfs rw,noexec,nosuid,nodev 0 0
none /sys/fs/fuse/connections fusectl rw 0 0
none /sys/kernel/debug debugfs rw 0 0
none /sys/kernel/security securityfs rw 0 0
udev /dev devtmpfs rw,mode=0755 0 0
devpts /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0
tmpfs /run tmpfs rw,noexec,nosuid,size=10%,mode=0755 0 0
none /run/lock tmpfs rw,noexec,nosuid,nodev,size=5242880 0 0
none /run/shm tmpfs rw,nosuid,nodev 0 0
none /run/user tmpfs rw,noexec,nosuid,nodev,size=104857600,mode=0755 0 0
/dev/md0 /mnt/md0 ext4 rw 0 0
root@ubuntu:~#

Setup the GRUB2 boot loader.

Create the file /etc/grub.d/09_swraid1_setup as follows:

[codesyntax lang="bash"]

cp /etc/grub.d/40_custom /etc/grub.d/09_swraid1_setup
vim /etc/grub.d/09_swraid1_setup

[/codesyntax]

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'Ubuntu, with Linux 3.5.0-17-generic' --class ubuntu --class gnu-linux --class gnu --class os {
    recordfail
    insmod mdraid1x
    insmod ext2
    set root='(md/0)'
    linux   /boot/vmlinuz-3.5.0-17-generic root=/dev/md0 ro   quiet
    initrd  /boot/initrd.img-3.5.0-17-generic
}

Make sure you use the correct kernel version in the menuentry (in the linux and initrd lines).

[codesyntax lang="bash"]

uname -r

[/codesyntax]

root@ubuntu:~# uname -r
3.5.0-17-generic
root@ubuntu:~#

Update grub configuration and adjust our ramdisk to the new situation:

[codesyntax lang="bash"]

update-grub
update-initramfs -u

[/codesyntax]

root@ubuntu:~# update-grub
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-3.5.0-17-generic
Found initrd image: /boot/initrd.img-3.5.0-17-generic
Found memtest86+ image: /boot/memtest86+.bin
done
root@ubuntu:~# update-initramfs -u
update-initramfs: Generating /boot/initrd.img-3.5.0-17-generic
W: mdadm: /etc/mdadm/mdadm.conf defines no arrays.
root@ubuntu:~#

Copy files to the new disk

Copy the files from the first disk (/dev/sda) to the second one (/dev/sdb)

[codesyntax lang="bash"]

cp -dpRx / /mnt/md0

[/codesyntax]

Preparing GRUB2 (Part 1)

Install GRUB2 boot loader on both disks (/dev/sda and /dev/sdb):

[codesyntax lang="bash"]

grub-install /dev/sda
grub-install /dev/sdb

[/codesyntax]

root@ubuntu:~# grub-install /dev/sda
Installation finished. No error reported.
root@ubuntu:~# grub-install /dev/sdb
Installation finished. No error reported.

Now we reboot the system and hope that it boots ok from our RAID arrays:

[codesyntax lang="bash"]

reboot

[/codesyntax]

Preparing /dev/sda

If everything went well, you should now find /dev/md0 in the output of:

[codesyntax lang="bash"]

df -h

[/codesyntax]

root@ubuntu:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/md0         19G  985M   17G   6% /
udev            494M  4.0K  494M   1% /dev
tmpfs           201M  304K  201M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            502M     0  502M   0% /run/shm
none            100M     0  100M   0% /run/user
root@ubuntu:~#

The output of:

[codesyntax lang="bash"]

cat /proc/mdstat

[/codesyntax]

root@ubuntu:~# cat /proc/mdstat 
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md1 : active raid1 sdb5[1]
      1045952 blocks super 1.2 [2/1] [_U]
      
md0 : active raid1 sdb1[1]
      19905408 blocks super 1.2 [2/1] [_U]
      
unused devices: <none>
root@ubuntu:~#

Change the partitions type on /dev/sda to Linux raid autodetect:

[codesyntax lang="bash"]

sfdisk --change-id /dev/sda 1 fd
sfdisk --change-id /dev/sda 5 fd

[/codesyntax]

root@ubuntu:~# sfdisk --change-id /dev/sda 1 fd
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
Done

root@ubuntu:~# sfdisk --change-id /dev/sda 5 fd
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
Done

root@ubuntu:~#

[codesyntax lang="bash"]

fdisk -l

[/codesyntax]

root@ubuntu:~# fdisk -l

Disk /dev/sda: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00059a4b

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048    39845887    19921920   fd  Linux raid autodetect
/dev/sda2        39847934    41940991     1046529    5  Extended
/dev/sda5        39847936    41940991     1046528   fd  Linux raid autodetect

Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *        2048    39845887    19921920   fd  Linux raid autodetect
/dev/sdb2        39847934    41940991     1046529    5  Extended
/dev/sdb5        39847936    41940991     1046528   fd  Linux raid autodetect

Disk /dev/md0: 20.4 GB, 20383137792 bytes
2 heads, 4 sectors/track, 4976352 cylinders, total 39810816 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/md0 doesn't contain a valid partition table

Disk /dev/md1: 1071 MB, 1071054848 bytes
2 heads, 4 sectors/track, 261488 cylinders, total 2091904 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/md1 doesn't contain a valid partition table
root@ubuntu:~#

Now we can add /dev/sda1 and /dev/sda5 to the respective RAID arrays:

[codesyntax lang="bash"]

mdadm --add /dev/md0 /dev/sda1
mdadm --add /dev/md1 /dev/sda5

[/codesyntax]

root@ubuntu:~# mdadm --add /dev/md0 /dev/sda1
mdadm: added /dev/sda1
root@ubuntu:~# mdadm --add /dev/md1 /dev/sda5
mdadm: added /dev/sda5
root@ubuntu:~#

Take a look at:

[codesyntax lang="bash"]

cat /proc/mdstat

[/codesyntax]

root@ubuntu:~# cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md1 : active raid1 sda5[2] sdb5[1]
      1045952 blocks super 1.2 [2/1] [_U]
          resync=DELAYED
      
md0 : active raid1 sda1[2] sdb1[1]
      19905408 blocks super 1.2 [2/1] [_U]
      [=======>.............]  recovery = 36.4% (7247872/19905408) finish=1.0min speed=205882K/sec
      
unused devices: <none>
root@ubuntu:~#

Then adjust /etc/mdadm/mdadm.conf to the new situation:

[codesyntax lang="bash"]

cp /etc/mdadm/mdadm.conf_orig /etc/mdadm/mdadm.conf
mdadm --examine --scan >> /etc/mdadm/mdadm.conf

[/codesyntax]

Display the content of /etc/mdadm/mdadm.conf:

[codesyntax lang="bash"]

cat /etc/mdadm/mdadm.conf

[/codesyntax]

root@ubuntu:~# cat /etc/mdadm/mdadm.conf
# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#

# by default (built-in), scan all partitions (/proc/partitions) and all
# containers for MD superblocks. alternatively, specify devices to scan, using
# wildcards if desired.
#DEVICE partitions containers

# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes

# automatically tag new arrays as belonging to the local system
HOMEHOST

# instruct the monitoring daemon where to send mail alerts
MAILADDR root

# definitions of existing MD arrays

# This file was auto-generated on Tue, 23 Oct 2012 04:36:40 -0700
# by mkconf $Id$
ARRAY /dev/md/0 metadata=1.2 UUID=89e5afc0:2d741a2c:7d0f40f0:a1457396 name=ubuntu:0
ARRAY /dev/md/1 metadata=1.2 UUID=ce9163fc:4e168956:5c9050ad:68f15735 name=ubuntu:1
root@ubuntu:~#

Preparing GRUB2 (Part 2)

Now it's safe to delete /etc/grub.d/09_swraid1_setup

[codesyntax lang="bash"]

rm -f /etc/grub.d/09_swraid1_setup

[/codesyntax]

Update our GRUB2 bootloader configuration and install it again on both disks (/dev/sda and /dev/sdb)

[codesyntax lang="bash"]

update-grub
update-initramfs -u
grub-install /dev/sda
grub-install /dev/sdb

[/codesyntax]

Reboot the machine

[codesyntax lang="bash"]

reboot

[/codesyntax]

 

Common commands for Foundry switches and load balancers

Publicat la 3 October 2012 No comments

General Commands

  • show run - shows the current (running) configuration
  • show config - shows the saved (startup) configuration
  • show int bri - quick status of all interfaces
  • show int eth 18 - detailed information on interface ethernet 18
  • show vlan - shows VLAN information and port association
  • show log - shows the log
  • show mac-address - shows the mac addresses
  • exit - leave the current mode

Configuration commands

  • enable - needed to make changes
  • conf t - go from exec to configuration mode
    • int eth 18 - go into interface editing mode for ethernet 18
    • port-name - set port name for a port
    • no port-name - erase the port's name
    • enable - enable the interface
    • disable - disable the interface
  • vlan 902 - go into vlan editing mode for vlan 902
    • untag eth 18 - add interface 18 to this vlan as an untagged port
    • tag eth 18 - add interface 18 to this vlan as a tagged port
    • no untag eth 18 - remove interface 18 from this vlan when it was an untagged port
  • write mem - write the current configuration to flash

Creating a VLAN
vlan <vlan #> name <name of vlan> by port

  • vlan 666 name cursed-vlan by port

Adding ports to a VLAN
First edit the vlan, with vlan 666

  • enable
  • conf t
    • vlan 666
    • untagged ethe 25 to 28 - this would add ports 25 through 28 inclusive to vlan numbered 666

Misc things

  • how to grep for something

| include

example to output lines in the config containing "mail". Note this doesn't seem to be available in older code versions.

sh run | include mail

  • find which vlan's your port is using

show vlan eth 0/1/16

Load balancer commands

  • show server real - shows state and stats of real servers
  • show server virtual - shows state and stats of virtual servers
  • show server - shows quick status of all virtual and real servers

Load balancer configuration

  • server real host1 - go into real server editing mode for real server host1
    • port smtp - add smtp port on this host
    • port smtp disable - remove smtp port from this host
  • server virtual virtualhost - go into virtual server editing mode for virtual server virtualhost
    • bind smtp host1 smtp - bind the smtp port on real host host1 to this virtual server
    • no bind smtp host1 smtp - unbind the smtp port on real host host1 from this virtual server

Deleting servers and virtual servers

  • no server real foo - deletes server foo
  • no server virtual foo - deletes VIP foo

Example load balancer configuration
First add the real hosts. We'll use real hosts mailhost1 and mailhost2 and a proto of smtp in this example:

[codesyntax lang="bash"]

server real mailhost1 1.2.3.3
 port default disable
 port smtp
 port smtp keepalive

server real mailhost2 1.2.3.4
 port default disable
 port smtp
 port smtp keepalive

[/codesyntax]

 

Then add the virtual host(s):
[codesyntax lang="bash"]

server virtual mailhost 1.2.3.5
 predictor least-conn
 port default disable
 port smtp
 bind smtp mailhost1 smtp mailhost2 smtp

[/codesyntax]

This creates a virtual server called mailhost listening on IP address 1.2.3.5. The VIP listens on the SMTP port and passes SMTP traffic to the real servers, mailhost1 and mailhost2.

How to determine what xenserver is pool-master

Publicat la 3 October 2012 No comments

[codesyntax lang="bash"]

xe host-param-get param-name=name-label uuid=`xe pool-list | grep master | awk '{print $4}'`

[/codesyntax]

How to log bash history with syslog

Publicat la 1 October 2012 No comments

There are two methods to get this thing done.

1. Trap method - drop the following snippet into either the per-user or system-wide bash profile (~/.bash_profile or /etc/profile, respectively)

unset HISTSIZE HISTFILESIZE
export HISTTIMEFORMAT='%F %T'
function log2syslog
{
   declare COMMAND
   COMMAND=$(fc -ln -0)
   logger -p local1.notice -t bash -i -- "${USER}:${COMMAND}"
}
trap log2syslog DEBUG

2. Prompt Method - this method logs by hacking the prompt command to call history and write to syslog.

PROMPT_COMMAND='history -a >(tee -a ~/.bash_history | logger -t "$USER[$$] $SSH_CONNECTION")'

How to authenticate on a machine with ssh (protocol 1) without password

Publicat la 1 October 2012 No comments

This document describes the necessary steps to be carried out in order to authenticate with ssh protocol 1 without password.

1. Generate private/public pair of keys on client computer (let's say desktop)
[codesyntax lang="bash"]

ssh-keygen -t rsa1

[/codesyntax]

2. Copy the public key to the server
[codesyntax lang="bash"]

ssh-copy-id -i identity.pub user@server

[/codesyntax]

3. Try to authenticate on server
[codesyntax lang="bash"]

ssh -1 -vvv server

[/codesyntax]

Note: If authenticate on step 3 fails with the following error message:

user@user:~/.ssh$ ssh -1 -vvv user@server
OpenSSH_5.3p1 Debian-3ubuntu7, OpenSSL 0.9.8k 25 Mar 2009
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to staging13.vendio.com [10.111.0.236] port 22.
debug1: Connection established.
debug1: identity file /home/user/.ssh/identity type 0
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: Remote protocol version 1.5, remote software version 1.2.27
debug1: no match: 1.2.27
debug1: Local version string SSH-1.5-OpenSSH_5.3p1 Debian-3ubuntu7
debug2: fd 3 setting O_NONBLOCK
debug1: Waiting for server public key.
debug1: Received server public key (768 bits) and host key (1024 bits).
debug3: check_host_in_hostfile: filename /home/user/.ssh/known_hosts
debug3: check_host_in_hostfile: match line 1014
debug3: check_host_in_hostfile: filename /home/user/.ssh/known_hosts
debug3: check_host_in_hostfile: match line 1015
debug1: Host 'staging13.vendio.com' is known and matches the RSA1 host key.
debug1: Found key in /home/user/.ssh/known_hosts:1014
debug1: Encryption type: 3des
debug3: Wrote 156 bytes for a total of 194
debug1: Sent encrypted session key.
debug2: cipher_init: set keylen (16 -> 32)
debug2: cipher_init: set keylen (16 -> 32)
debug1: Installing crc compensation attack detector.
debug1: Received encrypted confirmation.
debug3: Wrote 20 bytes for a total of 214
debug1: RSA authentication using agent refused.
debug1: Trying RSA authentication with key '/home/user/.ssh/identity'
debug3: Wrote 268 bytes for a total of 482
Connection closed by X.X.X.X

And the sshd log on looks like:
Aug 29 00:26:21 staging13 sshd[16286]: connect from Y.Y.Y.Y
Aug 29 00:26:21 staging13 sshd[16286]: log: Connection from Y.Y.Y.Y port 43749
Aug 29 00:26:21 staging13 sshd[16286]: log: Could not reverse map address Y.Y.Y.Y.
Aug 29 00:26:22 staging13 sshd[16286]: fatal: RSA key has too many bits for RSAREF to handle (max 1024).

You should know that this is a limitation in the RSAREF library and we should set a host key with at most 896 bits. This can be accomplished by adding -b 896 parameter to ssh-keygen command on step one. After generating the key, it must be copied on the server.

Fixing the annoying "perl: warning: Setting locale failed" error message

Publicat la 1 October 2012 No comments

 This is what I get:

[codesyntax lang="bash"]

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LANG = "en_US.utf8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").

[/codesyntax]

 This is how I fix it:

[codesyntax lang="bash"]

export LANGUAGE=en_US.UTF-8
export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8
locale-gen en_US.UTF-8
apt-get install locales
dpkg-reconfigure locales

[/codesyntax]

The export lines above can also be saved into either ~/.profile or ~/.bashrc.