Vital Solaris Commands Interview Preparation Guide

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Collection of metadevices which have their own metadb

/var/adm directory contains Administration information
i)system crashes
ii) accounting information for eace user
iii)Logins

/var/sadm directory contains all the package related
information

we can create 8192 non global zones within global zone but
in realtime environment only at max of 10 to 15 is possible

We can use dladm command to change network interface
property in Solaris

In this example below maximum bandwidth of link is set to
2Mbps

$ dladm set-linkprop -p maxbw=2m e1000g0

Similarly if you want to set the link to full duplex
$ dladm set-linkprop -p duplex=full e1000g0

Advantages of Disksuite

Solstice disk suite provides three major functionalities :

1. Over come the disk size limitation by providing for
joining of
multiple disk slices to form a bigger volume.


2. Fault Tolerance by allowing mirroring of data from one
disk to another
and keeping parity
information in RAID5.


3. Performance enhancement by allowing spreading the data
space over
multiple disks .

There are two ways to add swap in Sun Server(i.e. Sun
Solaris) as below;

1. Make a partion at availbale free disk of required swap
size and then make an entry in /etc/vfstab file. After that
run the command #swapadd /dev/dsk/cXtXdXsX or give the
reconfiguration reboot to the Server.

2. Instead of making partion you can create make a file of
required swap size with the help of #mkfile <size>
<filename> command and after that make an entry
in /etc/vfstab and follow rest of steps mention in point
one.

Zones: A zone is a virtual operating system abstraction
that provides a secured environment where applications
run.The applications are protected from each other to
provide software fault isolation.

Container: zone + resource management
The ability to control resource usage for processes,task
and zones.Resources can be CPU level,RAM,virtual
memory,Kernel level tables etc.

There two common errors or problems you will encounter in SVM and these are

1.Maintainence mode( Due to lack of syncronization or some other error)

2.Disk faulty is the second one!

run #devfsadm cmd after fix 80gb HDD
format.
plz wait disk is reading ..
the attached disk menstioned below controller with HDD name
selectt disk
c#t#d#
select p ( partition)
select p ( print)

you select tag 4 enter
you select tag name enter
you seletct wm enter
you select starting cylinder enter
you give now cylinder size : 65gb( you must mention mb or
gb) enter

u give l for lable ( lable means save a things)
it asking (y/n ) y

newfs /dev/rdsk/c#t#d#s4 enter
it taking few mins then crete dir for mount
mkdir /john ( anything )
mount /dev/dsk/c#t#d#s4 /john

and check
df -hk

put entry in /etc/vfstab

OKprintenv

- OpenBoot will be in diagnostic mode and the diagnostic-
mode? command will return true when the configuration
variable diag-switch is set TRUE.

- Diagnostic Test Commands

1) watch-net % To check network connections
2) test net % To test network conection
3) probe-scsi % To find the devices attached to SCSI BUS.

raid is also called redudant array of endependent disk it
is a combination of multiple disk and drive .which can
store a data in diffrent form and level.and it is confirm
the level of data avilability and data performance.
types of raid
raid 1,2,3,5,6,0+1,1+0

The situation when two or more clusters cannot
communicate with each other and each node thinks that it
owns the resources is said to be split brain scenario.

#haconf -makerw
#hagrp -freeze <group name> -persistent
#haconf -dump -makero

#hagrp –switch <service group name> -to <system name>

To start an agent: #haagent - start agentname -sys
To start cluster : #hastart
Configuration file: /etc/VRTSvcs/conf/config/main.cf

Sun Cluster

1) Kernel-based – Fatser in failure detection
2) It runs only on Solaris systems ( Platform dependent)

Veritas Cluster

1)Software based
2)Works on multiple OS ( Platform independent)

Depends on the taste of the guy and budget they have
to implement the cluster.

Never worked on all but can give below answer if you
have worked on any of them:
1) Sun Cluster
2) Veritas cluster
3) HACMP – High Availability Cluster Multiprocesing

SVM

1)Comes by default with Solaris 9/10
2)We cannot shrink volume in SVM

VxVM

1) Third party software where we need to install it
2) We can shrink volume in VxVM

During the solaris boot process once it reads
the /etc/system file and is supposed to boot from veritas
volumes below are the two lines that need to be placed
in /etc/system file such that it boot using veritas root
device.
1. rootdev:/pseudo/vxio@0:0
2. set vxio:vol_rootdev_is_volume=1

Source: Symantec Docs
Detach State
Detaching a plex leaves the plex associated with its
volume, but prevents normal volume I/O from being directed
to the plex. This operation can be applied to plexes that
are enabled or disabled. The rules for performing the
detach depend upon the usage types of the volumes involved.
The operation does not apply to dissociated plexes.

Disassociate State
Dissociate each of the named plexes. Dissociating a plex
breaks the link between the plex and its volume. A
dissociated plex is inaccessible until it is reassociated,
which can be done either with vxplex att or with vxmake.
Any checks and synchronizations that apply to the det
operation also apply to the dis operation.
Plex dissociation is the normal means of unmirroring a
volume, or reducing the mirror count for a volume. To
support this use, -o rm can be used to dissociate and
remove the plex (and its associated subdisks) in the same
operation. This makes the space used by those subdisks
usable for new allocations (such as with vxassist or with
vxmake).

Plex dissociation can also be used for file system backups
of volumes that are normally mirrored. Plex devices are not
directly mountable, so the backup method described for the
det operation will not work if the backup program requires
a mounted file system. To support such backup programs, a
plex can be dissociated and can then be allocated to a new
volume, such as with the command:

vxmake -U gen vol volume plex=plex
The created volume can then be started and mounted for use
by the backup program.

Can be removed using vxdiskadm and select option 5 (
To replace a failed disk)
23. Plex is in a disabled state. How will you recover? what
are the steps to follow?
Ans: 1) Place the plex in CLEAN state #vxmend -g dg
fix clean fix
2) To recover other plexes in a volume from CLEAN plex
#vxmend -g dg fix stale plex
3) Enable CLEAN plex # vxvol -g dg start volume

Failing disk

1) It shows read/write errors in /var/adm/messages.
2) As the time passes we can see increased number of hard
and transport error when checkd by iostat -En.
3)We can see the disk available when format is used

Failed disk
1)It shows “ disk not responding to selection” message
2)It only shows the increased transport errors
3)Format command displays “ disk not available” message

First check how much space you can increase using
#vxassist -g <diskgroup> maxgrow
After checking how much you can increase we can use the
below commands to increase volume
#vxassist -g <diskgroup> growby <volume> <len_to_grow_by>
or
#vxassist -g <diskgroup> growto <volume> <new_len>