Oracle related podcasts worth listening to

Posted on May 26, 2011 by Bjoern Rost

My morning commute consists of a lot of traffic and I like to spend my time listening to all kinds of podcasts. Of course, I also tried most (if not all) of Oracle’s podcasts. Two of them stayed subscribed and I’d like to mention them here.

Servers, Storage, and Solaris talks about all aspects of former SUN products like sparc and x86 servers and blade systems, virtualization, Solaris and Storage technology. Some of them seem a little bit scripted by marketing people but it is still great to listen to engineers and product managers talk about their products.

The other one that stuck is Oracle Technology Network TechCasts. In this well-produced podcast series, Justin Kestelyn interviews or introduces people highly involved and enthusiastic with Oracle technology. Since OTN covers the whole array of products from hardware to applications, some of the topics may not be of interest to everybody. But the ones that cover interesting topics are full of valuable information and fun to listen to.

Cisco NetNoGo

Posted on May 6, 2011 by Bjoern Rost

I get a huge load of comercial mails from network, hardware and software vendors that tell me to check the latest results of some very important benchmark you have never heard of, download a biased whitepaper or attend a useless webcast with sales people. Most of these messaged end up in trash really fast but I did like Cisco’s most recent campaign. It did make me smile, read the whole thing and even watch the video. I am still not signing up for their webcast though.

IPv6 in Solaris Zones

Posted on May 5, 2011 by fbh

When we upgraded our datacenters to full native IPv6 we also began to enable IPv6 on our Solaris servers.

What works really well on global Solaris zones and on Solaris LDOMs can be a big pain on shared Solaris zones.

So what is the catch with Solaris zones? When you create a new Solaris zone you can add an IPv6 address easily the same way you add an IPv4 address but as you may know IPv6 needs a so called ‘link-local’ address to work properly or else IPv6 Neighbor Discovery won’t work.

We got 2 problems here. When you use an auto configured route on the global zone the shared zone will know about it (cause they share the network stack) but can’t use it since it is an link-local route and the shared zone don’t have an link-local interface. This problem can easily be avoided by setting a route to a global address in the global zone. Now the shared zone knows about the correct gateway but that is where we get to the second problem. The shared zone can neatly resolve the MAC address of the router via ND but the router can not resolve the MAC address of the zone via ND. When you snoop on the interface on the global zone you will see that the “neighbor solicitation” request arrives on the interface but somehow it is not answered.

So how do we get around the second problem? We have to add another IPv6 address to the shared zone – a link-local one. How does this usually look like? The link-local segment is fe80::/10. Usually the link-local address is generated on an per interface basis the following way: fe80::xxxx:xxxx:xxxx:xxxx/10 where xxxx:xxxx:xxxx:xxxx is the modified EUI-64 address. Since the modified EUI-64 address is already used by link-local interface in the global zone we have to come up with another address. In our case I just use the following address for our shared zones: fe80::xxxx/10. Where in this case xxxx is the last 32bit of our global IPv6 address of the zone. Lets assume our global IPv6 address for the zone is 2001:db8:0:113::133/64 this would make our link-local address for that zone fe80::133/10.

This is what a shared config zone with IPv6 global and link-local address could look like:

root@solaris10u9:~# zonecfg -z test info
zonename: test
zonepath: /zp01/zones/test
brand: native
autoboot: true
bootargs:
pool:
limitpriv:
scheduling-class:
ip-type: shared
hostid:
inherit-pkg-dir:
        dir: /lib
inherit-pkg-dir:
        dir: /platform
inherit-pkg-dir:
        dir: /sbin
inherit-pkg-dir:
        dir: /usr
net:
        address: 203.0.113.133
        physical: aggr1
        defrouter not specified
net:
        address: 2001:db8:0:113::133/64
        physical: aggr1
        defrouter not specified
net:
        address: fe80::133/10
        physical: aggr1
        defrouter not specified

With this setup we now got fully working IPv6 in Solaris shared zones.

Make sendmail on Solaris 10 listen to more than localhost

Posted on May 4, 2011 by Bjoern Rost

I was just installing a new sendmail server and once again stumbled across the default solaris config that will only bind this service to localhost. I knew this could be fixed somewhere in the svc properties but since this is not my daily cup of tea, I had to google this and it took me a few minutes. Anyway, this is what I came up with:

svccfg -v -s sendmail setprop config/local_only=false svcadm refresh sendmail svcadm restart sendmail

I found it at this blog.