Re: HACMP 5.3 relies over /etc/hosts files!?



Marlon,

Just think about:

Which is most probable: /etc/hosts file damaged or DNS communication
failure?

The reason why is recommended to have all IP addresses defined @
/etc/hosts file over all cluster nodes is because in any given moment when
you lost DNS services (through network), you (and so the cluster) become
unable to resolve the many IP addresses.

My recommendation for /etc/netsvc.conf:

hosts=local,bind

This configuration should force name resolution through /etc/hosts first ,
and then DNS.






MARLON BORBA <MBORBA@xxxxxxxxxxx>
Sent by: IBM AIX Discussion List <aix-l@xxxxxxxxxxxxx>
30/03/2006 18:03
Please respond to IBM AIX Discussion List

To: aix-l@xxxxxxxxxxxxx
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Subject: HACMP 5.3 relies over /etc/hosts files!?


Dear AIX gurus,

Reading the "HACMP Cookbook" [1] I've found a surprising statement:

"It is good practise to have all the above IP addresses defined in
/etc/hosts file and this file the same on all nodes in the cluster. There
is certainly no requirement to use fully qualified names. While HACMP is
processing network changes, the NSORDER variable is set to local (i.e.,
pointing to /etc/hosts), however it is also good practice to set this in
/etc/netsvc.conf."

Does it mean that in a HACMP cluster one should not use DNS-resolvable
names? What if for some reason the /etc/hosts is damaged or compromised?



[1] http://www.redbooks.ibm.com/redbooks/pdfs/sg246769.pdf

Abraços,
Marlon Borba, CISSP.
--
Se você acha que a criptografia pode resolver
todos os seus problemas de segurança,
então você não conhece os seus problemas
e nem a criptografia.
(Bruce Schneier)
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