Wednesday, July 30, 2014

Iscsi Intiator + Multipath

Install the Packages

yum -y install iscsi-initiator-utils
yum install device-mapper-multipath -y
/etc/init.d/multipathd start
/etc/init.d/iscsid start

chkconfig multipathd on
chkconfig iscsid on

#Discover the target.
iscsiadm -m discovery -t sendtargets -p

iscsiadm -m discovery -t sendtargets -p

# creating new iscsi interface
iscsiadm -m iface -I iscsi-eth1 -o new

iscsiadm -m iface -I iscsi-eth2 -o new

iscsiadm -m iface -I iscsi-eth1 -o update -n iface.net_ifacename -v eth1

iscsiadm -m iface -I iscsi-eth2 -o update -n iface.net_ifacename -v eth2

#login to all discovered targets
iscsiadm -m node -l
#to Create the multipath config file automatically

#multipath -F

#else Create a file /etc/multipath.conf with the following content:

echo "
defaults {
udev_dir /dev
polling_interval 10
path_selector "round-robin 0"
path_grouping_policy multibus
path_checker readsector0
rr_min_io 100
max_fds 8192
rr_weight priorities
failback immediate
no_path_retry fail
user_friendly_names yes

" >> /etc/multipath.conf
[root@controller1 ~]# /etc/init.d/multipathd restart
Stopping multipathd daemon: [ OK ]
Starting multipathd daemon: [ OK ]
[root@controller1 ~]# multipath -ll
mpatha (36a4badb00053ae7f0000f49e53d73254) dm-3 DELL,MD3000i
size=250G features='3 queue_if_no_path pg_init_retries 50' hwhandler='1 rdac' wp=rw
|-+- policy='round-robin 0' prio=6 status=active
| |- 4:0:0:2 sdb 8:16 active ready running
| `- 5:0:0:2 sdc 8:32 active ready running
`-+- policy='round-robin 0' prio=1 status=enabled
|- 3:0:0:2 sde 8:64 active ghost running
`- 6:0:0:2 sdd 8:48 active ghost running
[root@controller1 ~]#
#Add Following to /etc/multipath.conf
multipaths {
multipath {
wwid 36a4badb00053ae7f0000f49e53d73254
alias lun0
path_grouping_policy multibus
path_checker readsector0
path_selector "round-robin 0"
failback manual
rr_weight priorities
no_path_retry fail

[root@controller1 ~]# multipath -ll
Jul 29 07:11:45 | multipath.conf line 20, invalid keyword: path_checker
lun0 (36a4badb00053ae7f0000f49e53d73254) dm-3 DELL,MD3000i
size=250G features='3 queue_if_no_path pg_init_retries 50' hwhandler='1 rdac' wp=rw
|-+- policy='round-robin 0' prio=6 status=active
| |- 4:0:0:2 sdb 8:16 active ready running
| `- 5:0:0:2 sdc 8:32 active ready running
`-+- policy='round-robin 0' prio=1 status=enabled
|- 3:0:0:2 sde 8:64 active ghost running
`- 6:0:0:2 sdd 8:48 active ghost running
[root@controller1 ~]#

#List the All DISK's which will include ISCSI drive
fdisk -l

# Use Mkfs to create the file system and mount it using _netdev option


More iscsiadm commands

iscsiadm -m session

iscsiadm -m node -u

targets configuration will be in /var/lib/iscsi

GFS - Global File System from Redhat + Iscsi drive sharing.

# install packages

yum groupinstall -y "High Availability"
yum install -y cman gfs2-utils modcluster ricci luci cluster-snmp iscsi-initiator-utils openais oddjob rgmanager

On each node create a cluster config file

# /etc/cluster/cluster.conf
<?xml version="1.0"?>
<cluster config_version="3" name="cluster1">
<clusternode name="node1" nodeid="1"/>
<clusternode name="node2" nodeid="2"/>

passwd ricci
chkconfig iptables off
#or configure the Ports to be opened.
chkconfig ip6tables off
chkconfig ricci on
chkconfig cman on
chkconfig rgmanager on
chkconfig modclusterd on
service iptables stop
service ip6tables stop
service ricci start
service cman start
service rgmanager start
service modclusterd start

service ricci restart
service cman restart
service rgmanager restart
service modclusterd restart
# for node1 only
chkconfig luci on
service luci start

[root@controller1 ~]# chkconfig luci on
vice luci start[root@controller1 ~]# service luci start
Adding following auto-detected host IDs (IP addresses/domain names), corresponding to `controller1' address, to the configuration of self-managed certificate `/var/lib/luci/etc/cacert.config' (you can change them by editing `/var/lib/luci/etc/cacert.config', removing the generated certificate `/var/lib/luci/certs/host.pem' and restarting luci):
(none suitable found, you can still do it manually as mentioned above)

Generating a 2048 bit RSA private key
writing new private key to '/var/lib/luci/certs/host.pem'
Start luci... [ OK ]
Point your web browser to https://controller1:8084 (or equivalent) to access luci
[root@controller1 ~]#

Making GFS file system
/sbin/mkfs.gfs2 -j 10 -p lock_dlm -t cluster1:GFS /dev/sdb

Mounting the partion
# edit /etc/fstab and append the following.
/dev/sdb /path_to_mount gfs2 defaults,noatime,nodiratime 0 0

Monday, July 28, 2014

Windows Commands


assoccmd2 15 CMD Commands Every Windows User Should Know
Most files in Windows are associated with a specific program that is assigned to open the file by default. At times, remembering these associations can become confusing. You can remind yourself by entering the command “assoc” to display a full list of file extensions and the programs they’re connected with.
You can also extend the command to change file associations. For example, “assoc .txt=” will change the file association for text files to whatever program you enter after the equal sign. The ASSOC command itself will reveal both the extension names and program names, which will help you properly use this command. You can probably do this more easily in the GUI, but the command line interface is a perfectly functional alternative.

ciphercmd 15 CMD Commands Every Windows User Should Know
Deleting files on a mechanical hard drive doesn’t really delete them at all. Instead, it marks the files as no longer accessible and the space they took up as free. The files remain recoverable until they’re overwritten with new data, which can take some time.
The cipher command, however, can be used to wipe a directory by writing random data to it. To wipe your C drive, for example, you’d use the command “cipher /w:c”, which will wipe free space on the drive. The command does not overwrite undeleted data, so you will not wipe out files you need by running this command.
There’s also a host of other cipher commands, however, they are generally redundant with Bitlocker enabled versions of Windows.

driverquerycmd 15 CMD Commands Every Windows User Should Know
Drivers remain among the most important software installed on a PC. Improperly configured or missing drivers can cause all sorts of trouble, so its good to have access to a list of what’s on your PC. That’s exactly what the “driverquery” command does. You can extend it to “driverquery -v” to obtain more information including the directory in which the driver is installed.
File Compare

This command can be used to identify differences in text between two files, and is particularly useful for writers and programmers trying to find small changes between two versions of a file. Simply type “fc” and then the directory path and file name of the two files you want to compare.
fccmd 15 CMD Commands Every Windows User Should Know
You can also extend the command in several ways. Typing “/b” compares only binary output, “/c” disregards the case of text in the comparison, and “/l” only compares ASCII text.
So, for example, you could use the following:
fc /l "C:\Program Files (x86)\example1.doc" "C:\Program Files (x86)\example2.doc"
to compare ASCII text in two word documents.

This command relays the IP address that your computer is currently using. However, if you’re behind a router (like most computers today), you’ll instead receive the local network address of the router.
Still, ipconfig is useful because of its extensions. “ipconfig /release” followed by “ipconfig /renew” can force your Windows PC into asking for a new IP address, which is useful if your computer claims one isn’t available. You can also use “ipconfig /flushdns” to refresh your DNS address. These commands are great if the Windows network troubleshooter chokes, which does happen on occasion.

Entering the command “netstat -an” will provide you with a list of currently open ports and related IP addresses. You’ll also be told what state the port is in – listening, established or closed. This is a great command if you’re trying to troubleshoot the devices your PC is connected to or you’re afraid you’re infected with a Trojan and are trying to locate a malicious connection.'


pingcmd 15 CMD Commands Every Windows User Should Know
Sometimes, you need to know whether or not packets are making it to a specific networked device. That’s where ping comes in handy. Typing “ping” followed by an IP address or web domain will send a series of test packets to the specified address. If they arrive and are returned, you know the device is capable of communicating with your PC; if it fails, you know that there’s something blocking communication between the device and your computer. This can help you decide if an issue is caused by improper configuration or a failure of network hardware.

This is a more advanced version of ping that’s useful if there are multiple routers between your PC and the device you’re testing. Like ping, you use this command by typing “pathping” followed by the IP address, but unlike ping, pathping also relays some information about the route the test packets take.

tracertcmd 15 CMD Commands Every Windows User Should Know
The “tracert” command is similar to pathping. Once again, type “tracert” followed by the IP address or domain you’d like to trace. You’ll receive information about each step in the route between your PC and the target. Unlike pathping, however, tracert also tracks how much time (in milliseconds) each hop between servers or devices takes.

Powercfg is a very powerful command for managing and tracking how your computer uses energy. You can use the command “powercfg /hibernate on” and “powercfg /hibernate off” to manage hibernation, and you can also use the command “powercfg /a” to view the power-saving states currently available on your PC.
Another useful command is “powercfg /devicequery s1_supported” which displays a list of devices on your computer that support connected standby. When enabled, these devices can be used to bring your computer out of standby – even remotely. You can enable this by selecting the device in Device Manager, opening its properties, going to the Power Management tab and then checking the “Allow this device to wake the computer” box.
“Powercfg /lastwake” will show you what device last woke your PC from a sleep state. You can use this command to troubleshoot your PC if it seems to wake from sleep at random.
powercfgcmd 15 CMD Commands Every Windows User Should Know
The “powercfg /energy” command can be used to build a detailed power consumption report for your PC, which is output to a directory indicated after the command finishes. This report will let you know of any system faults that might increase power consumption, like devices that are blocking certain sleep modes, or which aren’t properly configured to respond to your power management settings.
Windows 8 added “powercfg /batteryreport”, which provides a detailed analysis of battery use, if applicable. Normally output to your Windows user directory, the report provides details about the time and length of charge and discharge cycles, lifetime average battery life, and estimated battery capacity.'

As of Windows 8/8.1 there is now a shutdown command that – you guessed it! – shuts down your computer. This is of course redundant with the already easily accessed shutdown button, but what’s not redundant is the “shutdown /r /o” command, which restarts your PC and launches the Advanced Start Options menu, which is where you can access Safe Mode and Windows recovery utilities. This is useful if you want to restart your computer for troubleshooting purposes.
System File Checker

System File Checker is an automatic scan and repair tool that focuses on Windows system files. You will need to run the command prompt with administrator privileges and enter the command “sfc /scannow”. If any corrupt or missing files are found, they’ll be automatically replaced using cached copies kept by Windows for just that purpose. The command can require a half-hour to run on older notebooks.
Recovery Image

recimgcmd 15 CMD Commands Every Windows User Should Know
Virtually all Windows 8/8.1 computers ship from the factory with a recovery image, but the image may include bloatware you’d rather not have re-installed. Once you’ve un-installed the software you can create a new image using the “recimg” command. Entering this command presents a very detailed explanation of how to use it. You must have administrator privileges to use the recimg command, and you can only access the custom recovery image you create via the Windows 8 “refresh” feature.

The “tasklist” command can be used to provide a current list of all tasks running on your PC. Though somewhat redundant with Task Manager, the command may sometimes find tasks hidden from view in that utility.
tasklist 15 CMD Commands Every Windows User Should Know
There’s also a wide range of modifiers. “Tasklist -svc” shows services related to each task, “tasklist -v” can be used to obtain more detail on each task, and “tasklist -m” can be used to locate .dll files associated with active tasks. These commands are useful for advanced troubleshooting.

Tasks that appear in the “tasklist” command will have an executable and process ID (a four-digit number) associated with them. You can force stop a program using “taskkill -im” followed by the executable’s name, or “taskkill -pid” followed by the process ID. Again, this is a bit redundant with Task Manager, but may be used to kill otherwise unresponsive or hidden programs.

Friday, July 25, 2014

NIC Bonding in linux

#Creating Bonding Channel
echo "alias bond0 bonding" >> /etc/modprobe.d/bonding.conf
options bond0 miimon=80 mode=5
Be sure to add this before any of the network aliases

mode=0 (Balance Round Robin)
mode=1 (Active backup)
mode=2 (Balance XOR)
mode=3 (Broadcast)
mode=4 (802.3ad)
mode=5 (Balance TLB)
mode=6 (Balance ALB)
#Creating Channle Bonding Interface
echo "
" >> /etc/sysconfig/network-scripts/ifcfg-bond0

echo "
" /etc/sysconfig/network-scripts/ifcfg-eth1

echo "
" /etc/sysconfig/network-scripts/ifcfg-eth2

Managing Two Gateway in Linux Environment using routing rules


cat /etc/iproute2/rt_tables
echo "# dual nic-gateway below" >> /etc/iproute2/rt_tables
echo "10 routetable15" >> /etc/iproute2/rt_tables
cat /etc/iproute2/rt_tables

echo " dev eth3 src table routetable15
default via dev eth3 table routetable15
" >> /etc/sysconfig/network-scripts/route-eth3
echo "
from table routetable15
to table routetable15
" >> /etc/sysconfig/network-scripts/rule-eth3


cat /etc/iproute2/rt_tables
echo "# dual nic-gateway below" >> /etc/iproute2/rt_tables
echo "11 routetable17" >> /etc/iproute2/rt_tables
cat /etc/iproute2/rt_tables

echo " dev eth1 src table routetable17
default via dev eth1 table routetable17
" >> /etc/sysconfig/network-scripts/route-eth1
echo "
from table routetable17
to table routetable17
" >> /etc/sysconfig/network-scripts/rule-eth1

Monday, July 21, 2014

Neutron + Pacemaker for HA Gives error

I was trying to configure HA for neutron server in icehouse implementation. I was able to set up ha for all other services except neutron. I was trying to use pacemaker for setting up HA  by following

but still i get following error. dhcp agent and metadata agent is showing no error but l3 agent is not working.

output of crm_mon -1
Last updated:FriJul1814:03:252014Last change:FriJul1813:54:042014 via cibadmin on network1 Stack: classic openais (with plugin)Current DC: network2 - partition with quorum Version:1.1.10-14.el6_5.3-368c7262Nodes configured,2 expected votes 4Resources configured

Online:[ network1 network2 ]

p_api-ip (ocf::heartbeat:IPaddr2):Started network2

p_neutron-dhcp-agent (ocf::openstack:neutron-dhcp-agent):Started network1

p_neutron-metadata-agent (ocf::openstack:neutron-metadata-agent):Started network1

Failed actions: p_neutron-l3-agent_start_0 on network2 'unknown error'(1): call=13, status=TimedOut,last-rc-change='Fri Jul 18 04:32:06 2014', queued=20091ms,exec=0ms p_neutron-l3-agent_start_0 on network1 'unknown error'(1): call=23, status=TimedOut,last-rc-change='Fri Jul 18 14:03:01 2014', queued=20010ms,exec=0ms[root@network1 openstack]#


The neutron-agent-l3 script to blame as it tries to communicate with neutron server
directly on port 9696, while communication is handled by AMQP service
(Qpid in my case). We need to modify the script to use Qpid port and not neutron server one.

Friday, July 18, 2014

Neutron Network Issue. Gateway not pinging for the external network.

In Network  node

ip netns

Above command will give the virtual router's as you can see my output below. From that select the qrouter ID and try command

ip netns exec <qrouter-id> ip addr

ip netns exec <qrouter-id> route -n

The above commands should show IP's in virtual router and routing table of qrouter.

make sure your routing table shown as has a gateway. Or else try setting it using

ip netns exec <qrouter-id> route add default gw *** *** *** ***

ip netns exec <qrouter-id> iptables save



Thursday, July 10, 2014

Configure Amazon CloudWatch Monitoring Scripts for Linux

Installing dependencies

yum install cpan
yum install perl-Time-HiRes
cpan >> install Switch
yum install zip unzip
yum install wget
yum install perl-Crypt-SSLeay

cd aws-scripts-mon/

vi awscreds.template

Test it
./ --mem-util --mem-used --mem-avail --disk-path=/ --disk-space-util --disk-space-used --disk-space-avail --swap-used --aws-credential-file=/root/aws-scripts-mon/awscreds.template

Add it to cron
* * * * * /usr/bin/perl /root/aws-scripts-mon/ --mem-util --mem-used --mem-avail --aws-credential-file=/root/aws-scripts-mon/awscreds.template --from-cron