How to test ISCSI speed and capture trace for ISCSI nic on XenServer

In this blog I am going to talk about test throughput of ISCSI lun and then capture the packet on storage interface. Later on these packets can be open via wireshark.

In the above example first do find out lun which is currently mapped by running ll /dev/mapper. In my case it is the first one .

Now use the command to read the file size of 10MB *100 time which is like 1GB of date read from the lun . At the same time run tcpdump command on the same XenServer (Basically two ssh session ) on nic which is connected to the storage sub system . In my case it is xenbr8 . This can also be determined by running "route " command.

Do the same to determine  write speed . There would be two .pcap file under root which you can import using winscp and latter can be open via wireshark . When it open via wireshark it shows complete path for packet transfer

How to create LUN on EMC VNX 5500 and assign it to XenServer host.

In my last post I explained how to map iSCSI interface from XenServer to VNX 5500 box. In this post I will explain how to create lun and map it to the XenServer Cluster.

Launch Unisphere console and select the box. Choose storage and from drop down select "LUNs". This will bring to the page where all the created lun will be listed. Hit "Create"

 

This will pop one box asking for information like

Storage Pool Type : It is better to choose pool

Raid type : This is defined while creating pool and I am not going to explain those details in my post as this post is

                       meant  creation and attaching lun to XenServer.

Storage Pool for new LUN: Again this is created when commissioning of storage.

Capacity will show space for each of the pool separately, not over all storage.

Rest is self explanatory. Under "Advance" tab make sure you choose "Auto" and this way you don't have to bother about owner of the LUN. As you know VNX 5500 is active passive storage.  

Tiering should be set to "Auto" as it will automate fail over process.

Once LUN is created you need to assign to the storage group. Assuming that respective Storage group is already created.

Once LUN is assigned to the storage  group . Then we have to assign host to the storage group . It  same place from where you can create Storage group. Select the respective Storage Group and click properties . Choose the hosts tab , from here move the available host to the connected host list . This will assign LUN tot he respective XenServer.

LUN tab will which SP is the owner of the LUN. There is also a state during the SP fail over which SP will own the  LUN .

How to update HOSTNAME on Dell IDRAC for PowerEdge M710HD server

Sometimes it is quite tough to find simple stuff on quite popular sites. May be I am stupid or may be its poor documentation. I was trying to update hostname as shown below because by default the hostname would be localhost.

In order to update this , boot the Dell server and press Ctrl+ E when you get below boot menu

This will bring iDRAC configuration utility . I was thinking this somewhere you can do from desktop. Yeah stupid of me. So choose "LAN Parameters" and then "Host Name String". It will popup box for hostname. Provide correct host name and exit with saving changes.

How to map iSCSI interface of XenServer 6.0.2 to EMC VNX 5500

I am starting series of blog with hastag "DellEMCXEN "which will talks about integrating XenServer with EMC VNX 5500. XenServer is installed on Dell Power Edgem710 HD with Chassis M1000e connected via Nexus 5500 and Dell switch M8024.

First define storage interface on XenServer and for that choose configure under "Management Interface " and then select "New Interface" . Now specify the name and then choose the NIC which will be configure for storage traffic. Supply IP address. This needs to be repeated for all the interface which is connected to the storage.

Once this is done then perform discovery of the nic for the logging into EMC. This can be perform via CLI as well as via XenCenter. To perform via XenCenter select new storage and choose "Software iSCSI". Choose "Name" and then under location provide information as follows :

Target host: This will be IP address of target Storage Processor or controller . Specify all the IP address with ,

Target IQN: Here you will find IQN of the target storage processor . If it has 4 ports then you will see 4 IQN. We need to choose the one which is highlighted (*)

This will log all the targets on the EMC VNX box to mapped .

From the command line following  needs to be run from the host in order to login.

Once all the message says successfully login , open EMC Unixshpere and select "Connectivity status "  on left hand side under "Hosts ". This will popup Host initiators window. You will find one name with just IQN as shown below. This is the new targets which has logged in . Select "Edit " from bottom and then provide information about "host name" "IP address" . IP address is of  XenServer  management IP . Make sure you choose initiator type as "clarion open " and Fail Over mode as "ALUA 4". ALUA is the latest fail over mode as per EMC and other storage vendors.

With this host will be connected to to EMC storage. In the next series , I will explain process of creating lun and attaching it to the storage group.

Forcibly take control of Dell -IDRAC console access

Some people have a bad habit of taking control of DRAC access and locking their workstation . If someone want to have access they have to wait till gentleman comes back and provide him so. One way its good but other way its frustrate other.

We can forcibly take control of session by resetting the console access . You can do this at your own risk :) . Launch the weblogin and press the tab "Reset iDRAC6"