Tuesday, 19 November 2013

Solaris Interview Questions

1) Can you reduce a FS in VxVM ? What is the risk involved ?
2) What are branded zones in solaris ?
3) What is the main enhancement in NFS v4 over v3 ?
4) How can we refresh automount config without affecting connected users ?
5) How many types of automount maps are there ?
6) How can you patch a solaris zone which is a sparse root ?

7) What is the difference between zone and container in Solaris ?
8) How can we assign zpool to NGZ ?
9) How thin provisioning / sparse volume is created in ZFS ?


10) Suppose after a power outage or a mistake by storage admin, one of your LUN in VxVM was unavailable and now it has become available again. But your mountpoint is throwing I/O error. How will you resolve this situation ?
11) What are the advantages of using ZFS instead of UFS ?
12) Which is better hardware  RAID or software RAID ? why ?
13) After a power outage or kernel panic ZFS pool is not getting imported ? What are the steps for troubleshooting this ?
14) Which virtualization solution would you recommend to customer LDOM or zones ? under what scenario and considerations ?
15) Suppose you have a low memory condition on solaris server . How will you troubleshoot further ?
16) What is the change in regards to network configuration in Solaris 10 over Solaris 8 ?

17) How can you restore LDOM configuration ?
18) How can we clone LDOM ?
19) Which field of iostat indicates a IO bottleneck ? What are the important metrics to be looked at in iostat output ?
20) In maintaining Solaris security what are the common steps / procedures followed by System Admins ?
21) In Solaris we have resource pools ( rpool ). We can assign rpools to zones as well to set cpu shares. Then why do we need resource controls in zones ( add rctl ) . What is the advantage of using resource controls when resource pooling is already there ?
22) How to install multiple patches in a single patchadd invocation ?   

Monday, 18 November 2013

VCS VXVM DiskGroup switchover example



Step 1:- Start the desired haagent ( DiskGroup) on both the machines.

client1: /tmp/vcs> haagent -start DiskGroup -sys client1
client1: /tmp/vcs> haagent -start DiskGroup -sys client2

Step 2:- Add the servicegroup and populate the SystemList.

client1: /tmp> haconf -makerw
client1: /tmp> hagrp -add DG_servicegroup
VCS NOTICE V-16-1-10136 Group added; populating SystemList and setting the Parallel attribute recommended before adding resources
client1: /tmp> hagrp -modify VG_servicegroup SystemList client1 1 client2 2

Step 3:- Add the resource, specify the type of the resource and assign it to a servicegroup, enable the resource, specify the Disk Group name etc and bring the resource online.

client1: /tmp> hares -add VXVMDG DiskGroup DG_servicegroup
VCS NOTICE V-16-1-10242 Resource added. Enabled attribute must be set before agent monitors
client1: /tmp> hares -modify VXVMDG Enabled 1
client1: /tmp> hares -modify VXVMDG DiskGroup clusterdg
client1: /tmp> hares -modify VXVMDG StartVolumes 1
client1: /tmp> hares -online VXVMDG -sys client1

Step 4:- Add a ‘Mount’ resource type named clustervol ( or whichever name it is easy to identify with ), specify the correct blockdevice name, FS type, mountpoint and fsck option. Enable and bring the resource online.

client1: /tmp> hares -add clustervol Mount DG_servicegroup
VCS NOTICE V-16-1-10242 Resource added. Enabled attribute must be set before agent monitors
client1: /tmp> hares -modify clustervol BlockDevice /dev/vx/dsk/clusterdg/clustervol
client1: /tmp> hares -modify clustervol FSType vxfs
client1: /tmp> hares -modify clustervol MountPoint /clustervol
client1: /tmp> hares -modify clustervol FsckOpt %-y
client1: /tmp> hares -modify clustervol Enabled 1
client1: /tmp> hares -online clustervol -sys client1

Step 5 :- Link the two resources i.e “DiskGroup and Mount” and enable resources contained with the servicegroup.

client1: /tmp> hares -link clustervol VXVMDG
client1: /tmp> hagrp -enableresources DG_servicegroup
client1: /tmp> hagrp -online DG_servicegroup -sys client1
client1: /tmp> haconf -dump –makero
client2: /tmp> mkdir /clustervol
client1: /tmp> hagrp -switch DG_servicegroup -to client2