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Thursday, October 13, 2016
9:44:00 AM
Friday, October 7, 2016
How to check bad wrong login attempts in HPUX
Requirement :
To check bad / wrong login attempts done on HPUX server.
Howto :
HPUX server logs all wrong logins information in /var/adm/btmps file. This file is data file hence commands like cat, more wont work for this file. To read data within this file use below command
This will convert data in btmps file in human readable format (binary to ASCII). Later you can cat or more output file and investigate bad logins.
Important fields here are :
To check bad / wrong login attempts done on HPUX server.
Howto :
HPUX server logs all wrong logins information in /var/adm/btmps file. This file is data file hence commands like cat, more wont work for this file. To read data within this file use below command
# /usr/sbin/acct/fwtmp -X < /var/adm/btmps > /tmp/badlogins.log
This will convert data in btmps file in human readable format (binary to ASCII). Later you can cat or more output file and investigate bad logins.
# cat /tmp/badlogins.log
root pts/ta 12127 0 0000 0000 1190171137 0 Sep 19 11:05:37 2007 0 10.105.100.89 10.105.100.89
root pts/tb 13964 0 0000 0000 1190174185 0 Sep 19 11:56:25 2007 0 10.105.100.89 10.105.100.89
Important fields here are :
- ID which tried to log in
- Terminal from which attempt was made
- Date time stamp when attempt was made
- IP from which attempt came to server (last field)
Thursday, October 6, 2016
Adding extra or secondary swap in HPUX
 |
| Freeimages |
adding extra swap before you think of adding RAM to server which involves cost/resources of parent machine.
Step 1.
For adding extra swap check how much space you have available in root volume group vg00. Use vgdisplay command to get free PE and PE size numbers.
# /usr/sbin/vgdisplay vg00
--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 9
Open LV 9
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 4384
VGDA 4
PE Size (Mbytes) 16
Total PE 6544
Alloc PE 5978
Free PE 566
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
Here we have 566 free PE with 16MB size of each. This sums upto 8.8GB of free space in root vg. We can use space from this 8.8GB for adding extra swap.
Check current swap configuration
# /usr/sbin/swapinfo -tam
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 43008 0 43008 0% 0 - 1 /dev/vg00/lvol2
reserve - 1963 -1963
memory 40861 9261 31600 23%
total 83869 11224 72645 13% - 0 -
Step 2.
Create new contiguous logical volume with no bad block relocation policy and size of your requirement. Lets make a LV of 2GB.
# lvcreate -L 2048 -C y -r n /dev/vg00
Logical volume "/dev/vg00/lvol10" has been successfully created with character device "/dev/vg00/rlvol10"
Step 3.
Start swap on this lvol. Add -f argument to start forcefully if below command fails.
# swapon -p 1 /dev/vg00/lvol10
Step 4.
Edit /etc/fstab to mount this LV as swap on every boot. Add below entry :
/dev/vg00/lvol10 ... swap pri=1 0 1
Step 5.
Check again swap size.
# /usr/sbin/swapinfo -tam
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 43008 0 43008 0% 0 - 1 /dev/vg00/lvol2
dev 2048 0 2048 0% 0 - 2 /dev/vg00/lvol10
reserve - 1963 -1963
memory 40861 9261 31600 23%
total 85917 11224 74693 13% - 0 -
Wednesday, October 5, 2016
Adding new storage LUN to integrity virtual machine (iVM) in HPUX
Steps to add new LUN into integrity virtual machine (iVM) in HPUX and use it within existing VG or create a new VG on it.In this process, storage luns are always presented to physical host server. from host they are attached to virtual guest server running on it.Step 1.
Identify new LUN on HP iVM host server. When new LUN is presented to iVM, run ioscan command to scan new disks. Post ioscan, run insf command to make sure all available hardware has its related files created in kernel.
# ioscan -fnCdisk
# insf -e
Now your new LUN is identified in kernel. Match lun id in storage utility (syminq in case of EMC
storage, evainfo in case of HP EVA storage etc) and get related disk number. We are using agile naming convention here so lets take /dev/rdisk/disk10 & /dev/rdisk/disk11 are new identified disks.
storage, evainfo in case of HP EVA storage etc) and get related disk number. We are using agile naming convention here so lets take /dev/rdisk/disk10 & /dev/rdisk/disk11 are new identified disks.
Step 2.
Make disks LVM ready by using pvcreate.
# pvcreate /dev/rdisk/disk10
Physical volume "/dev/rdisk/disk10" has been successfully created.
# pvcreate /dev/rdisk/disk11
Physical volume "/dev/rdisk/disk11" has been successfully created.
Step 3.
Attach these disks to iVM (guest) which is running on host. Assume vmserver1 is our iVM here.
# hpvmmodify -P vmserver1 -a disk:avio_stor::disk:/dev/rdisk/disk10
# hpvmmodify -P vmserver1 -a disk:avio_stor::disk:/dev/rdisk/disk11
Step 4.
Once above commands are successful, disks are attached to iVM and needs to scan in guest. Login to iVM server and scan the new disks the same way we did in step 1 and 2 on host. Lets say those disks are identified as /dev/rdisk/disk2 & /dev/rdisk/disk3 on guest server. Observe those are identified as Virtual disk on vm.
disk 6 0/0/0/0.2.0 sdisk CLAIMED DEVICE HP Virtual Disk
/dev/dsk/c0t2d0 /dev/rdsk/c0t2d0
disk 8 0/0/0/0.3.0 sdisk CLAIMED DEVICE HP Virtual Disk
/dev/dsk/c0t3d0 /dev/rdsk/c0t3d0
Step 5.
Complete LVM tasks on these disks to use space in mount point.
To create new VG named vg01
# mkdir /dev/vg01
# mknod /dev/vg01/group c 64 0x010000
# vgcreate -s 64 -p 60 -e 12500 vg01 /dev/disk/disk2 /dev/disk/disk3
Volume group "/dev/vg01" has been successfully created.
Volume Group configuration for /dev/vg01 has been saved in /etc/lvmconf/vg01.conf
# lvcreate -L 200 /dev/vg01
Logical volume "/dev/vg01/lvol1" has been successfully created with
character device "/dev/vg01/rlvol1".
# newfs -F vxfs -o largefiles /dev/vg01/rlvol1
version 7 layout
204800 sectors, 204800 blocks of size 1024, log size 1024 blocks
largefiles supported
# mkdir /data
# mount /dev/vg01/lvol1 /data
To extend current existing VG named vg02 & mount point /data1 within it
# vgextend vg02 /dev/disk/disk2 /dev/disk/disk3
Volume group "vg02" has been successfully extended.
Volume Group configuration for /dev/vg02 has been saved in /etc/lvmconf/vg02.conf
# lvextend -L 512 /dev/vg02/lvol1
Logical volume "/dev/vg02/lvol1" has been successfully extended.
Volume Group configuration for /dev/vg02 has been saved in /etc/lvmconf/vg02.conf
# fsadm -F vxfs -b 524288 /data1
vxfs fsadm: V-3-23585: /dev/vg02/rlvol1 is currently 7731200 sectors - size will be increased
Tuesday, October 4, 2016
HPUX Patch naming conventions
HP release OS patches for HPUX every 6 month i.e. twice a year. For smaller patches which are releases as on need basis HP follows below naming conventions
Patch name format is PHxx_yyyy
Where,
xx = area of patch
CO : General HPUX commands
KL : Kernel patches
NE : Network specific patch
SS : all other subsystem patches
yyyy = unique number
From patch name you will be able to guess area of its impact so that you can plan your activities accordingly.
Monday, October 3, 2016
Basics of LVM legends
LVM (logical volume manager) legends :
One or more PV come together to form a Volume Group. This grouping enables to slice down combined
storage capacity of disks to our choice of small volumes. In above example vg00 is volume group made up of single PV & its sliced down to 8 LV (only one shown in above exmaple)
LE is Logical Extent.
Same as PE, LE are smallest chunk of LV.
Below tables gives you idea about some numbers related to them:
LVs per VG range : 1-255, default : 255
PVs per VG range : 1-255, default : 16
PEs per VG range : 1-66535 default : 1016
with above table, as max PE size is 64MB and 66,535 PEs max per VG, one can create max of 64x66353=4TB of file system.
PV is Physical Volume.
Any single disk / LUN on system is identified as PV. It can be raw or formatted with file system. Raw PV is referred as /dev/rdsk/c0t0d1 (legacy) or /dev/rdisk/disk1 (agile) whereas formatted one is referred as /dev/dsk/c0t0d1 (legacy) or /dev/disk/disk1 (agile). Check PV name in below output as formatted device.
# vgdisplay -v vg00
--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 13
Open LV 13
Max PV 16
Cur PV 1
Act PV 1
Max PE per PV 4355
VGDA 2
PE Size (Mbytes) 32
Total PE 4345
Alloc PE 4303
Free PE 42
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
--- Logical volumes ---
LV Name /dev/vg00/lvol1
LV Status available/syncd
LV Size (Mbytes) 1024
Current LE 32
Allocated PE 32
Used PV 1
--- Physical volumes ---
PV Name /dev/dsk/c3t0d0s2
PV Status available
Total PE 4345
Free PE 42
Autoswitch On
Proactive Polling On
PE is Physical Extent.
Its smallest chunk of PV which can be used as block under file system. PV is consist of number of PEs. We always use PV names while using LVM commands. In above example PE size is set to 32MB & total 4345 PEs are available on disk.
VG is Volume Group.
One or more PV come together to form a Volume Group. This grouping enables to slice down combined
LV is Logical Volume.
Its a slice of volume group using some capacity of PV to form a smaller volume. Its basically used as a mount point /swap like drives (C:, D:) in Windows. We can see one LV in above example and its details.
LE is Logical Extent.
Same as PE, LE are smallest chunk of LV.
Below tables gives you idea about some numbers related to them:
LVs per VG range : 1-255, default : 255
PVs per VG range : 1-255, default : 16
PEs per VG range : 1-66535 default : 1016
with above table, as max PE size is 64MB and 66,535 PEs max per VG, one can create max of 64x66353=4TB of file system.
Sunday, October 2, 2016
Account lock unlock status in Linux
Requirement :
To check current password status of account in Linux
Solution :
1. To check if account is locked or not.
Below are two examples of command outputs when account is locked and when account is not locked.
2. Lock account manually.
3. Unlock account manually.
To check current password status of account in LinuxSolution :
1. To check if account is locked or not.
Below are two examples of command outputs when account is locked and when account is not locked.
# passwd -S user1
user1 LK 2016-10-01 0 90 7 -1 (Password locked.)
# passwd -S user1
user1 PS 2016-10-01 0 90 7 -1 (Password set, MD5 crypt.)
# cat /etc/shadow |grep -i user1
user1:$1$ZFXgKhSG$lroasdrS0QM4iji.4h1:17075:0:90:7::: <--- Account is not locked
# cat /etc/shadow |grep -i user1
user1:!!$1$ZFXgKhSG$lroasdrS0QM4iji.4h1:17075:0:90:7::: <---Account is locked
# passwd -l user1
Locking password for user user1.
passwd: Success
3. Unlock account manually.
# passwd -u user1
Unlocking password for user user1.
passwd: Success.
Saturday, October 1, 2016
Password file commands
Here are the list of commands which can be used on /etc/passwd file.
vipw
pwck
pwconv
It generates /etc/shadow file which has user passwords in encrypted format under second field in each user entry. If /etc/shadow file already exist on system then this command will update relevant fields if there were any changes in /etc/passwd file. If your system is trusted (see tsconvert command) then user password database (Trusted Computing Database) is being maintained separately and /etc/shadow doesn't exist on system. In that case, this command will update the TCB accordingly.
pwunconv
It reverse the changes made by pwconv command.
vipw
This command is being used to edit /etc/passwd file manually. It is not recommended to edit /etc/passwd file manually. All changes on user accounts should be carried out using commands like usermod. But in some scenario if you want to edit passwd file manually, then use this command. It opens file in vi editor and locks it for other users. So any other admin from any other terminal wont be able to open the file in editor for manual editing. This ensures integrity of file.
pwck
To check integrity of /etc/passwd file this command can be used. Once executed it checks passwd files and its all fields. It reports any issues observed in the file e.g. if user directory does not exist on server, it will report it.
# /usr/sbin/pwck
[/etc/passwd] sfmdb:*:107:20::/home/sfmdb:/sbin/sh
Login directory not found
[/etc/passwd] smmsp:*:109:20::/home/smmsp:/sbin/sh
Login directory not found
pwconv
It generates /etc/shadow file which has user passwords in encrypted format under second field in each user entry. If /etc/shadow file already exist on system then this command will update relevant fields if there were any changes in /etc/passwd file. If your system is trusted (see tsconvert command) then user password database (Trusted Computing Database) is being maintained separately and /etc/shadow doesn't exist on system. In that case, this command will update the TCB accordingly.
# /usr/sbin/pwconv
Updating the tcb to match /etc/passwd, if needed.
pwunconv
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