why db2level and db2licm is extremely slow if network is down?

Harishkumar .Pathangay

why db2level and db2licm is extremely slow if network is down?

Hi,

I am observing that db2level, db2 list db directory and db2licm is extremely slow if network is down. it takes 30 sec.

Could not understand why? as these are local commands. what are they looking for in the network?

this happens only in CentOS and not in any other OS. I am running servers in VBox with Bridged Adapter Mode with static IP configuration.

So why it is so slow. Ubuntu Server is also configured the same way, but it is not slow at all. Only db2 on CentOS is slow. Why? why local command execution is very slow.

thanks,

harish pathangay

Nadir Doctor

why db2level and db2licm is extremely slow if network is down?
(in response to Harishkumar .Pathangay)
Hi Harish,

There is no official support for centos yet - just red hat, suse and ubuntu
only:

https://www-01.ibm.com/support/docview.wss?uid=swg27038033


Best Regards,
Nadir



On Sat, Sep 9, 2017 at 3:28 AM, Harishkumar .Pathangay <[login to unmask email]
> wrote:

> Hi,
>
> I am observing that db2level, db2 list db directory and db2licm is
> extremely slow if network is down. it takes 30 sec.
>
> Could not understand why? as these are local commands. what are they
> looking for in the network?
>
> this happens only in CentOS and not in any other OS. I am running servers
> in VBox with Bridged Adapter Mode with static IP configuration.
>
> So why it is so slow. Ubuntu Server is also configured the same way, but
> it is not slow at all. Only db2 on CentOS is slow. Why? why local command
> execution is very slow.
>
> thanks,
>
> harish pathangay
>
> -----End Original Message-----
>

Harishkumar .Pathangay

why db2level and db2licm is extremely slow if networkis down?
(in response to Nadir Doctor)
Okay.
But my humble opinion is the same behaviour will be there in Red Hat too.
I do not have RH Linux as it is licensed. Is there any trial version that you know of?
I will try that.

Sent from Mail for Windows 10

From: Nadir Doctor
Sent: 09 September 2017 18:47
To: [login to unmask email]
Subject: [DB2-L] - RE: why db2level and db2licm is extremely slow if networkis down?

Hi Harish,

There is no official support for centos yet - just red hat, suse and ubuntu only:

https://www-01.ibm.com/support/docview.wss?uid=swg27038033



Best Regards,
Nadir
 


On Sat, Sep 9, 2017 at 3:28 AM, Harishkumar .Pathangay <[login to unmask email]> wrote:
Hi,
I am observing that db2level, db2 list db directory and db2licm is extremely slow if network is down. it takes 30 sec.
Could not understand why? as these are local commands. what are they looking for in the network?
this happens only in CentOS and not in any other OS. I am running servers in VBox with Bridged Adapter Mode with static IP configuration.
So why it is so slow. Ubuntu Server is also configured the same way, but it is not slow at all. Only db2 on CentOS is slow. Why? why local command execution is very slow.
thanks,
harish pathangay


Site Links: View post online   View mailing list online   Start new thread via email   Unsubscribe from this mailing list   Manage your subscription  

This email has been sent to: [login to unmask email]
Setup a data refresh task in less time than it takes to make a cup of coffee + save up to 90% in CPU
ESAi's BCV5 & XDM fast data refresh & Test Data Mgmt products will make you a hero to users. See
http://www.ESAIGroup.com/idug

Use of this email content is governed by the terms of service at:
http://www.idug.org/p/cm/ld/fid=2




Site Links: View post online   View mailing list online   Start new thread via email   Unsubscribe from this mailing list   Manage your subscription  

This email has been sent to: [login to unmask email]
Setup a data refresh task in less time than it takes to make a cup of coffee + save up to 90% in CPU
ESAi's BCV5 & XDM fast data refresh & Test Data Mgmt products will make you a hero to users. See
http://www.ESAIGroup.com/idug

Use of this email content is governed by the terms of service at:
http://www.idug.org/p/cm/ld/fid=2


Attachments

  • 296E83DC6D8F42CAA3A3F9FFC663C9C6.png (<1k)
  • D54ED409190742DFA61B80627D4FDD37.png (<1k)

Harishkumar .Pathangay

RE: why db2level and db2licm is extremely slow if networkis down?
(in response to Harishkumar .Pathangay)

ok. please treat thread closed.

after I put /etc/hosts entry for static ip address , the db2 commands are running faster.

 

what I do not understand is why db2level or db2 list db directory needs network access to DNS server, for accessing locally available information. that's the question I have for db2 experts.

thanks,
harish pathangay

Harishkumar .Pathangay

RE: why db2level and db2licm is extremely slow if networkis down?
(in response to Harishkumar .Pathangay)

please have a look at the following video:

https://youtu.be/RD4oE6xMrDM

this describes the scenario that I have raised with example.

thanks,

harish pathangay

Ian Bjorhovde

why db2level and db2licm is extremely slow if networkis down?
(in response to Harishkumar .Pathangay)
Harish,

What do you have in /etc/nsswitch.conf, /etc/host.conf and
/etc/resolve.conf ? Many, many programs call make standard *nix system
calls like `gethostbyname()` that can be affected by incorrect system
configurations.



On Mon, Sep 11, 2017 at 6:22 AM, Harishkumar .Pathangay <
[login to unmask email]> wrote:

> please have a look at the following video:
>
> https://youtu.be/RD4oE6xMrDM
>
> this describes the scenario that I have raised with example.
>
> thanks,
>
> harish pathangay
>
> -----End Original Message-----
>

Harishkumar .Pathangay

RE: why db2level and db2licm is extremely slow if networkis down?
(in response to Ian Bjorhovde)

Hi Ian,

Thanks for your inputs and response.

thanks again for your inputs and spending your valuable time on this request.

I completely understand that the issue is with a bad network configuration or network issue. i have the fix also, all i need to do is put a entry in /etc/hosts file for my static ip so that if DNS is not reachable it can resolve locally. I get all that. But my question is why db2level, db2 interactive prompt, db2set [....] all commands are getting slower trying to look for network or DNS for local commands which is just reading a db dir file and displaying output.

The issue appears in Ubuntu 16.04 also [os supported by db2].

Here are the information asked:

-------------------------------------------------------------------------------------------------------------------------------------

more resolv.conf
# Generated by NetworkManager
nameserver 192.168.1.1

-------------------------------------------------------------------------------------------------------------------------------------

[[login to unmask email] etc]# more host.conf
multi on

-------------------------------------------------------------------------------------------------------------------------------------

[[login to unmask email] etc]# more nsswitch.conf
#
# /etc/nsswitch.conf
#
# An example Name Service Switch config file. This file should be
# sorted with the most-used services at the beginning.
#
# The entry '[NOTFOUND=return]' means that the search for an
# entry should stop if the search in the previous entry turned
# up nothing. Note that if the search failed due to some other reason
# (like no NIS server responding) then the search continues with the
# next entry.
#
# Valid entries include:
#
# nisplus   Use NIS+ (NIS version 3)
# nis   Use NIS (NIS version 2), also called YP
# dns   Use DNS (Domain Name Service)
# files   Use the local files
# db   Use the local database (.db) files
# compat   Use NIS on compat mode
# hesiod   Use Hesiod for user lookups
# [NOTFOUND=return] Stop searching if not found so far
#

# To use db, put the "db" in front of "files" for entries you want to be
# looked up first in the databases
#
# Example:
#passwd:    db files nisplus nis
#shadow:    db files nisplus nis
#group:     db files nisplus nis

passwd:     files sss
shadow:     files sss
group:      files sss
#initgroups: files sss

#hosts:     db files nisplus nis dns
hosts:      files dns myhostname

# Example - obey only what nisplus tells us...
#services:   nisplus [NOTFOUND=return] files
#networks:   nisplus [NOTFOUND=return] files
#protocols:  nisplus [NOTFOUND=return] files
#rpc:        nisplus [NOTFOUND=return] files
#ethers:     nisplus [NOTFOUND=return] files
#netmasks:   nisplus [NOTFOUND=return] files    

bootparams: nisplus [NOTFOUND=return] files

ethers:     files
netmasks:   files
networks:   files
protocols:  files
rpc:        files
services:   files sss

netgroup:   nisplus sss

publickey:  nisplus

automount:  files nisplus
aliases:    files nisplus

-------------------------------------------------------------------------------------------------------------------------------------

/etc/hosts File:
127.0.0.1  localhost.localdomain localhost
::1  localhost6.localdomain6 localhost6
#192.168.1.5 cos-vbox cos-vbox
127.0.1.1 localhost localhost

 

thanks again for your inputs and spending your valuable time on this request.

thanks,

harish pathangay