Infra structure notes

This page is intended to describe what are the relevant parts of the Tier-2/Tier-3 infra-structure (site specific notes), common problems/solutions that one might have and potential pitfalls

DNS

At the moment (05/2014) we have 2 DNSs - t2-headnode.local and t2-headnode-new.tier2. Each for its own domain - problem - they share the same subnet. As the new headnode is more flexible (not Rocks) I'm making the old a forwarder for the .local domain. It gets more complicated when one tries to do reverse DNS and the subnet is in theory the same. More after testing/improvements

Network

Description/Diagrams

Potential pitfalls

Switch ports might not work out of the box for DHCP/PXE. Although there was some suspicion towards Spanning Tree Protocol configuration, all we need is to watch for the following notes, described by Azher :

STP needs to be there in the network to avoid switching loops, its
mandatory when you have multiple links crossing equipment from different
vendors using old style STP. Newer technologies like fabric paths,
Qfabric etc avoids having STP.

Now when STP is enabled, you must put the edge port facing server/hosts
in a mode that when the link comes up, the port immediately starts
forwarding packets, a must for PXE / DHCP.

There are techniques to secure this behavior not to allow these edge
ports participating in STP and shut them down when you hear STP from them.

Services

DHCP in the backup server

We all know which is the server, the network team uses a DHCP server there. This will conflict with our Tier-2 DHCP after the 10.3.0.0/8 network was setup there. Probably the fix is to prevent DHCPD to bind to the private interface, to be tested.

-- Main.samir - 2014-05-13