Sanity Check

[timdeadman]

Hi

One of our customers has the following:

CSS 11150

ap0502003

ap10500099s

CSS1 and CSS2 balance the load to a server farm on VLAN100 to the north of the CSSs. To the south is VLAN 200. CSS 3 is not yet connected.

Server Farm

----------VLAN100------------

CSS1 CSS2 Css3

------------VLAN200----------

Users

CSS 1, CSS2 and CSS 3 are in different data centres and the data centre holding CSS 1 is going to close and a new data centre holding CSS 3 will open. VLAN 100 and 200 span all three data centres.

I want to install CSS 3 in the new data centre but have a couple of worries.

Worry 1

CSS1 is the master (VIP redundancy) and apparently CSS 2 has not been fully tested EVER. It has sat there fat and happy for about 18 months not really

doing anything. My plan is to "force master" CSS 2 and the leave it for a week or so to make sure it is stable and doing its job. Is there any command (such as IOS "sh tech support" ) that I can issue to check out CSS2 before I force it to be master? (I don't have login yet so I can't try it, I will have a login when I get to do the job but not at this planning stage)

Worry 2

When CSS 2 is master and we are all happy it is load balancing across the server farm, I want to bring up CSS 3 and take down CSS1. Is this the correct way to do it, in other words, can we put 3 CSS online using VRRP?

I hope you can help?

[jfoerster]

HI,

some thoughts about your worries:

Worry 1:

I thinkg there is nothing that is comparable with the sh tech of an IOS device. I guess you need to check it by hand by issung sh service, sh circuit and so to compare every single peace if it is working or not...

Because the config might look good but service might not be alive.. So I would compare the configs first and than verify if the services, owners content-rules are alive or not.

Worry 2:

If you are not planning to shutdown CSS1 then just configure the priority of the VRRP-Prozess so that it is the 3rd to come in place if CSS2/CSS3 are failing (see http://www.cisco.com/en/US/products/hw/contnetw/ps792/products_configuration_guide_chapter09186a008029b1da.html#wp1015553

and

http://www.cisco.com/en/US/products/hw/contnetw/ps792/products_command_reference_chapter09186a008028fd85.html#wp1139899)

This enables you to run all 3 boxes but in emergency case you might flip to CSS1 by forcing it to become master. IF CSS2/CSS3 prooved that they are running properly powerdown CSS1.

Kind Regards,

Joerg

[timdeadman]

Hi Joerg,

Thanks for that....Some very good advice there, I will let the forum know how it goes. Is it just me, or do these devices (CSS11000 range) make me more nervous than any other bits of kit I work with?

Tim

[jfoerster]

Hi Tim,

it's like anything else. The more you work with some boxes the more confident you get dealing with them. If you take care and do not rush through updates it's as safe to work with CSSes as with normal routers/switches;-)

Cheers,

Joerg