> If you need a different version of python then you lose because the iSCSI
> tools depend on a specific version of python and RHEL does not support
> installation of multiple versions.
AFAIK, RHEL provides the complete *working* software stack, also including iSCSI. It would surprise me if this also wasn't true for 6.2. I've recently done such a setup on a 6.1 setup.
> Serious bastion hosts should not have any unrequired software. Using RHEL
> makes that very difficult. RHEL 6.2 is probably even worse than older
RHEL is an enterprise OS. In RHEL terms, this means the supported packages will stay supported for at least 7 years since the first release major release. It basically means Red Hat is responsible for ensuring that the software packages they provide in RHEL will be supported during that whole life time.
> I really can't see the use case of pure software iSCSI anyway. iSCSI
> HBAs do not need that support and if money is a problem then ATAoE is
> *much* cheaper.
Pure software iSCSI is getting more and more used and available, even now on cheaper home NAS boxes. And Windows 7 (and probably Vista too, if somebody cares) have out-of-the-box iSCSI support too. That's something ATAoE doesn't provide so easily.
> Some very expensive routers support 10Gbe, and bonded 10Gbe, but not
> infiniband. If you have this equipment then bonded 10Gbe is cheaper than > IB.
Well, if you just measure throughput performance against a 10Gbit mark, you might be right. But if you take in consideration latencies and RDMA, infiniband is quite stronger. A single IB port may support QDR - Quad Data Rate, which is 40Gbit/s. No bonding needed.
For 10Gbe, you would need a NIC which supports RoCEE to get RDMA support. And you would need to bond 4 such NICs, to get somewhat closer to IB. But I'm not going to guarantee that this will give the exact same performance as a pure IB port in QDR, also not in latency. And I'm not sure the total price difference would be that much different, considering you probably need switches as well.