mpath

Mpath

Install, mount or unmount iscsi blockstorages with multipath. This have been tested on softlayer blockstorages. But will also work on other setups, with iscsi multipath storages.

The logic of this role is:

During installing

Install packages dependencies to use multipath and iscsi
Configure /etc/multipath.conf
Probe dm-multipath kernel module
Enable and start multipathd
List with (multipath -l) to trigger the multipathd handler
Configure /etc/iscsi/initiatorname.iscsi
Edit chap authentication on /etc/iscsi/iscsid.conf
Try to autologin on portal if fails use normal login
Create an alias on /etc/multipath/bindings
Mount multipath "/dev/mapper/mydeviceid" on "/mnt/myaliasname"
Trigger iscsi and iscsid to start and enable
Place the entries on /etc/fstab

During unmounting

Lsof pid's of device "/dev/mapper/mydeviceid"
If device are in use, force and release the device
Unmount device in lazy way (umount -l device)
Unmount and remove fstab entries
Flush multipath with (multipath -f device)
Logout from session portal target
Trigger handler to stop and disable iscsi,iscsid and multipathd services

Requirements

You will need a iscsi multipath blockstorage, the login and password for the iqn. You will also need the full initiator iqn path, and the iscsi mapper id. like: /dev/mapper/3600...

Role Variables

This are the variables you will need to adjust on your playbook.

iscsint is the initiator iqn name. e.g.:

iscsint: iqn.1994-05.com.redhat:47c98423c167

you can set multiples initiators as an array:

 iscsint:
   - iqn.1994-05.com.redhat:47c98423c167
   - iqn.1994-05.com.redhat:47c98423c167-2
   - iqn.1994-05.com.redhat:47c98423c167-3

mpathip is the target ipaddress

 mpathip: 10.150.10.20

filesystem: is default setted to ext4, change this to whatever you want.
Check supported filesystems on ansible mount module.

map: if setted to true, means all installation and config tasks will run.
If you set to false, the device mapper will be unmounted, and follow the unmount flux.

wwid is the alias for multipath device, and will be used to configure bindings file.
This variable is very important, it also will be used on whole role to mount and unmount device
based on id.

syntax must be:

wwid:
  - { id: '360009827346', alias: 'mylun0' }
  - { id: '360782378662', alias: 'mylun1' }
...

packs is the list of packages to install. It will install iscsi, multipath and lsof.

credetials must be adjusted on your playbook with your login and password.
e.g.

 credentials:
   - name: "My Credentials"
     login: mylogin
     pass: mypassword

WARNING!
login and password must be declared without quotation marks " or single quotes '.

Dependencies

None

Example Playbook

Here is a playbook sample. This playbook will install and mount multipath device on somehost:

- name: "Deploy | Running isca0.mpath role"
  hosts: somehost
  become: yes
  remote_user: myuser
  vars:
    mpathip: "10.200.10.100"
    credentials:
      - name: "Multipath"
        login: MyLogin
        pass: Mypassword
    iscsint:
      - "iqn.1994-05.com.redhat:47c98423c167"
    wwid:
      - { id: '3600a0980383888835645961', alias: 'blk' }
  roles:
    - mpath

If you want unmount a device on a group of hosts, and then mount on a exclusive host. You can run firstly a unmount playbook and then a "install/mount" playbook.

Here is a sample of unmount playbook:

- name: "Deploy | Running isca0.mpath role"
  hosts: groupofhosts
  become: yes
  remote_user: myuser
  vars:
    map: false
    mpathip: "10.200.10.100"
    wwid:
      - { id: '3600a098038303631a35645961', alias: 'blk' }
  roles:
    - mpath

As you can see, just set map to false, make the role to perform only the unmount tasks. :wink: