Run dr_install.sh script got error for Readahead size of sda (/dev/sdb1,/dev/sdb2) is too low for typical systems: 256 < 2048

Products

• CA Infrastructure Performance

Issue/Introduction

Run dr_install.sh script, got error for Readahead size of sda (/dev/sdb1,/dev/sdb2) is too low for typical systems: 256 < 2048

 

 	IM 2.3.4 	
 	Vertica 7 

 

When user tries to install/upgrade existing Vertica 6 to Vertica 7 via running script

 

 	./dr_install.sh -p drinstall.properties 

 

It shows up this error:

"
Failures during local (OS) configuration for verify-xx.xxx.xx.x.xml:
FAIL (S0020): https://my.vertica.com/docs/7.0.x/HTML/index.htm#cshid=S0020
Readahead size of sda (/dev/sdb1,/dev/sdb2) is too low for typical
systems: 256 < 2048
"

This is because Vertica 7 requires the Disk readahead by set to at least 2048.

User can run this command to check their disk:

 

 	# blockdev --report 	
 	RO RA SSZ BSZ StartSec Size Device 	
 	rw 2048 512 4096 0 128849018880 /dev/sda 	
 	rw 2048 512 1024 2048 524288000 /dev/sda1 	
 	rw 2048 512 4096 1026048 63899172864 /dev/sda2 	
 	rw 2048 512 4096 125829120 64424509440 /dev/sda3 	
 	rw 2048 512 4096 0 110066925568 /dev/dm-0 	
 	rw 2048 512 4096 0 17179869184 /dev/dm-1 	
 	rw 256 512 4096 0 134217728000 /dev/sdb 	
 	rw 256 512 1024 63 567512064 /dev/sdb1 	
 	rw 256 512 1024 1108485 69799726080 /dev/sdb2 

 

To modify above readahead value, use can run this command:

 

 	blockdev --setra <RA value> /dev/sdb 

 

For example:

 

 	blockdev --setra 2048 /dev/sdb 

 

then run the verify command again to check:

 

 	blockdev --report 	
 	RO RA SSZ BSZ StartSec Size Device 	
 	rw 2048 512 4096 0 128849018880 /dev/sda 	
 	rw 2048 512 1024 2048 524288000 /dev/sda1 	
 	rw 2048 512 4096 1026048 63899172864 /dev/sda2 	
 	rw 2048 512 4096 125829120 64424509440 /dev/sda3 	
 	rw 2048 512 4096 0 110066925568 /dev/dm-0 	
 	rw 2048 512 4096 0 17179869184 /dev/dm-1 	
 	rw 2048 512 4096 0 134217728000 /dev/sdb 	
 	rw 2048 512 1024 63 567512064 /dev/sdb1 	
 	rw 2048 512 1024 1108485 69799726080 /dev/sdb2 

 

Once the Disk readahead been set, above install error should be gone.

Environment

Release:
Component: CAPRFC

Resolution

To modify above readahead value, use can run this command:

 

 	blockdev --setra <RA value> /dev/sdb 

 

For example:

 

 	blockdev --setra 2048 /dev/sdb 

 

then run the verify command again to check:

 

 	blockdev --report 	
 	RO RA SSZ BSZ StartSec Size Device 	
 	rw 2048 512 4096 0 128849018880 /dev/sda 	
 	rw 2048 512 1024 2048 524288000 /dev/sda1 	
 	rw 2048 512 4096 1026048 63899172864 /dev/sda2 	
 	rw 2048 512 4096 125829120 64424509440 /dev/sda3 	
 	rw 2048 512 4096 0 110066925568 /dev/dm-0 	
 	rw 2048 512 4096 0 17179869184 /dev/dm-1 	
 	rw 2048 512 4096 0 134217728000 /dev/sdb 	
 	rw 2048 512 1024 63 567512064 /dev/sdb1 	
 	rw 2048 512 1024 1108485 69799726080 /dev/sdb2 

 

Once the Disk readahead been set, above install error should be gone.