settingup new machine to replace an old one

"Jan Gerrit Kootstra" <jan.gerrit.TakeThisOut@kootstra.org.uk> wrote in message
news:80903$4a1aeeb1$d55d2be5$15491@news.chello.nl...
> horus schreef:
>> Have RHEL4 on a Dell 1900 now rsyncing to
>>
>> RHEL5 2900........
>>
>> I want to shut off the old machine and have the new one
>> take its place in a kinda transparent way, so in theory all
>> I have to do is swap the IP numbers and reboot?
>> And maybe wait 10 min. for the local router arp cache
>> to renew.....
>>
>> does this sound correct?
>>
>>
>> thanks ahead of time
>>
>>
>> david
> David,
>
>
> Depends on what software is running on top of RHEL4.

Linux cosmos.sonoma.edu 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005
i686 i686 i386 GNU/Linux

thanks Jan, does this help?



david

horus schreef:
> "Jan Gerrit Kootstra" <jan.gerrit.DeleteThis@kootstra.org.uk> wrote in message
> news:80903$4a1aeeb1$d55d2be5$15491@news.chello.nl...
>> horus schreef:
>>> Have RHEL4 on a Dell 1900 now rsyncing to
>>>
>>> RHEL5 2900........
>>>
>>> I want to shut off the old machine and have the new one
>>> take its place in a kinda transparent way, so in theory all
>>> I have to do is swap the IP numbers and reboot?
>>> And maybe wait 10 min. for the local router arp cache
>>> to renew.....
>>>
>>> does this sound correct?
>>>
>>>
>>> thanks ahead of time
>>>
>>>
>>> david
>> David,
>>
>>
>> Depends on what software is running on top of RHEL4.
>
> Linux cosmos.sonoma.edu 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005
> i686 i686 i386 GNU/Linux
>
> thanks Jan, does this help?
>
>
>
> david
>
>
David,


That is the kernel version.

I mean things like Oracle 9i. So I mean which application(s) do you use.


Kind regards,


Jan Gerrit

>>>> Have RHEL4 on a Dell 1900 now rsyncing to
>>>>
>>>> RHEL5 2900........
>>>>
>>>> I want to shut off the old machine and have the new one
>>>> take its place in a kinda transparent way, so in theory all
>>>> I have to do is swap the IP numbers and reboot?
>>>> And maybe wait 10 min. for the local router arp cache
>>>> to renew.....
>>>>
>>> Depends on what software is running on top of RHEL4.
>>
>> Linux cosmos.sonoma.edu 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005
>> i686 i686 i386 GNU/Linux
>>
>
> I mean things like Oracle 9i. So I mean which application(s) do you use.


OH, well, those are all running fine, Apache, Sendmail, Dovecot, ntpd,
vsftpd, saslauthd, named....

I've tested each one personally (for 3 days of pounding)......

all the user data has been moved and is being rsync updated every 30 min.

My theory is, that swaping the IP's on each machine and rebooting them, with
a 10 min. pause for arp cache to clear from the network routers should do
it.

But I've always enjoyed a 2nd and more opinion as I'm getting up in years
and my logic isn't
what it used to be.

-

horus schreef:
>>>>> Have RHEL4 on a Dell 1900 now rsyncing to
>>>>>
>>>>> RHEL5 2900........
>>>>>
>>>>> I want to shut off the old machine and have the new one
>>>>> take its place in a kinda transparent way, so in theory all
>>>>> I have to do is swap the IP numbers and reboot?
>>>>> And maybe wait 10 min. for the local router arp cache
>>>>> to renew.....
>>>>>
>>>> Depends on what software is running on top of RHEL4.
>>> Linux cosmos.sonoma.edu 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005
>>> i686 i686 i386 GNU/Linux
>>>
>> I mean things like Oracle 9i. So I mean which application(s) do you use.
>
>
> OH, well, those are all running fine, Apache, Sendmail, Dovecot, ntpd,
> vsftpd, saslauthd, named....
>
> I've tested each one personally (for 3 days of pounding)......
>
> all the user data has been moved and is being rsync updated every 30 min.
>
> My theory is, that swaping the IP's on each machine and rebooting them, with
> a 10 min. pause for arp cache to clear from the network routers should do
> it.
>
> But I've always enjoyed a 2nd and more opinion as I'm getting up in years
> and my logic isn't
> what it used to be.
>
> -
>
>
Horus,


All the software you intend to run are distributed by Red Hat and
supported on RHEL5 so it should work fine.

I do not know how long the arp cache timeout is. A 10 min downtime might
not be enough, but let's see if a network specialist on this usenet
group will tell us otherwise.


Kind regards,


Jan Gerrit Kootstra

On May 27, 5:36 am, Jan Gerrit Kootstra <jan.ger... RemoveThis @kootstra.org.uk>
wrote:
> horus schreef:
>
> >>>>> Have RHEL4 on a Dell 1900       now rsyncing to
>
> >>>>> RHEL5 2900........
>
> >>>>> I want to shut off the old machine and have the new one
> >>>>> take its place in a kinda transparent way, so in theory all
> >>>>> I have to do is swap the IP numbers and reboot?
> >>>>> And maybe wait 10 min. for the local router arp cache
> >>>>> to renew.....
>
> >>>> Depends on what software is running on top of RHEL4.
> >>> Linux cosmos.sonoma.edu 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005
> >>> i686 i686 i386 GNU/Linux
>
> >> I mean things like Oracle 9i. So I mean which application(s) do you use.
>
> > OH,  well, those are all running fine, Apache, Sendmail, Dovecot, ntpd,
> > vsftpd, saslauthd, named....
>
> > I've tested each one personally (for 3 days of pounding)......
>
> > all the user data has been moved and is being rsync updated every 30 min.
>
> > My theory is, that swaping the IP's on each machine and rebooting them, with
> > a 10 min. pause for arp cache to clear from the network routers should do
> > it.
>
> > But I've always enjoyed a 2nd and more opinion as I'm getting up in years
> > and my logic isn't
> > what it used to be.
>
> > -
>
> Horus,
>
> All the software you intend to run are distributed by Red Hat and
> supported on RHEL5 so it should work fine.
>
> I do not know how long the arp cache timeout is. A 10 min downtime might
> not be enough, but let's see if a network specialist on this usenet
> group will tell us otherwise.
>

I'm not a network specialist, but....

The cache timeout is typically 10-20 minutes, but it should be
possible to force an update of other machines arp caches by pinging
them (anything on the same subnet which talks to the box). Certainly
no need to reboot after changing the IP address unless you have hard
coded local addresses in your server configs / iptables (even then
switching to runlevel 1 and back again will be quicker).

C.