ISCSI
Introduction
iSCSI is SCSI over IP. It is a standard described in RFC 3720 and 3783. The implementation is split into separate client-server components.
Components
iSCSI Initiator - client-side implementation to attach to iSCSI block devices over the network (IP).
iSCSI Target - server-side implementation to expose disks, partitions or volumes as block devices over the network.
Network Details
iSCSI normally uses the following default as per standards.
- Port: 3260
- Protocol: TCP
- Block size: 512 <= Adjustable
There are at least two major vendor implementations. One is by Cisco and the other by Intel.
Authentication
Most implementations support CHAP as authentication mechanism.
Operating system support
Microsoft
See Microsoft Support for iSCSI web page.
Microsoft provides a free "Initiator" utility which can be downloaded here.
Linux
Under Linux, the iSCSI statistics can be seen under /proc/scsi/iscsi
Ubuntu
Nothing available for Dapper (6.06) in base, universe or multiverse). Compile the open-iscsi by hand (see below).
For Feisty & later version, install open-iscsi from the universe repository.
Some time after that, the package names changes to open-iscsi-utils.
Red Hat
Package iscsi-initiator-utils is in the base. See Related Links for an iscsi-target setup. Read all the gory details at Installation and Design Notes for iSCSI RHEL 4 U2
CentOS
See Red Hat above.
Fedora / Fedora Core
See Red Hat above.
Debian
Recent development efforts have merged into open-iscsi.
OpenFiler
See http://www.openfiler.com/ iSCSI support is available in v2.3 and looks rather nifty.
Nexenta
Nexenta is a hybrid operating system combining OpenSolaris, Linux (Ubuntu) and ZFS.
Mac OS/X
Unknown
FreeBSD
There is an iscsi-target port available. This is merely a clone of the netbsd-iscsi port shown below. As of 7.0-RELEASE initiator support is available via iscsi_initiator(8) kernel module and iscontrol(4). See http://www.cyberciti.biz/faq/freebsd-iscsi-initiator-howto/
FreeNAS
Reported has iSCSI support. TBD.
Isilon
Isilon OneFS is based on FreeBSD and offers iSCSI target support.
NetBSD
There is an netbsd-iscsi package available as of 4.0.
See ftp://ftp.netbsd.org/pub/NetBSD/misc/agc/ for a couple of instructional HOWTOs.
OpenBSD
Unknown
Solaris & OpenSolaris
Unknown
AIX
Unknown
HP-UX
Unknown
Interoperability matrix
Please see our iSCSI Interoperability Matrix for viewing and adding compatibility entries.
Related Links
- Build an iSCSI target on CentOS-4...
- OpenFiler website...
- A Quick Guide to iSCSI on Linux...
- Creating a SAN with iSCSI...
- iSCSI Page @ (Wikipedia)...
- Microsoft Storage Technologies - iSCSI...
- Installation and Design Notes for iSCSI RHEL 4 U2
- Open iSCSI homepage
- iSCSI on FreeBSD (@ConchShell)
- Nexenta iSCSI performance notes
- Great iSCSI Info - blog posting about using OpenFiler with VMware ESX and link aggregation