Zyxel NSA 325 supported WiFi adapters


Digging around in the sources I found (boot time… ) hotplug handling for two WiFi adapters.

So if you’d like to have WiFi with your NSA325, look for the two models mentioned here:

##### Check if ZyXEL NWD-211AN (0586/3418) is plugged
grep “Vendor=0586 ProdID=3418” /proc/bus/usb/devices > /dev/null 2>&1

##### Check if ZyXEL NWD-270N (0586/341A) is plugged
grep “Vendor=0586 ProdID=341a” /proc/bus/usb/devices

TP-Link SG-3210 new firmware


TP-Link had released new firmware for this nice cheap 10-Port GigE managed switch back in January. I just found it and after doing a config backup, updated.

The new firmware seems to have some NTP improvements, still checking out what else has changed.

Warning:

All the config was _LOST_ during the update, putting the switch back to a initial configuration. You’ll find the management IP switches back to 192.168.0.1.

Well, do I care? no. It’s so quick to configure that I didn’t even bother to reload the config backup ๐Ÿ™‚

If you have a separate management VLAN and reach it only via a trunk port your mileage may vary.

Terabyte / hour backups


Backup is SO NOT boring.

A friend of mine told me about the confusion he caused among his colleagues.

With a bit of tuning he pushed the CommVault setup they had made from 700GB/h to 4TB/h.

Apparently they didn’t even really grasp what he changed ๐Ÿ™‚

Here are some old numbers of backup speed records I found with some google foo. What I really love about these is that it shows that you need a highly specialized systems vendor to really push numbers. It’s not enough to just “kill it with hardware”, and the current state-of-the-art for medium enterprise level is the record of 10 years ago (roughly, not even really)

SGI 1998:

1TB/hr (while system under TPC load…)

SGI 2003:

10.1TB/hr

Oracle 2011

9TB/s

restore: 77TB/s (deduped data)

 

For some of these there’s still some press releases and / or whitepapers to be found. I read them and forgot them already ๐Ÿ™‚

$90 TP-Link switch – wow


Today I got this tiny little switch from chinese TP-Link – and I’ll write a review here, since I’m having a hard time believing what this low-cost thinggy can do.

last time I bought something from that vendor was 5-6 years ago, some wireless cards with the FreeBSD-friendly Atheros chipset. Until recently their switches definitely didn’t look like anything you’d want to buy.

How I ended up with this one?

I always wanted to run fibre through the small hole I drilled into the living room wall so I could have a nice LACP+Vlan trunked interface to “teh server”, since that allows much more networking fun. The “normal” powerful switches like Cisco, Extreme, H3C I would have around are not suited for home use due to the amounts of power they are consuming to generate the noise the make ๐Ÿ™‚

A review of this tiny TP-Link switch in c’t had caught my attentionย since it listed having SNMPv3 support, plus two SFP ports.

Got the switch, took a moment to realize I would need to look at the manual to find the CLI port speed (38400 bps) and off we were!

Configuration is on the CLI mostly Cisco-link although at some points I didn’t manage to do it right on the CLI. For example I didn’t find out how to save the config ๐Ÿ™‚

From the web UI things are easier to configure, except maybe IP ACLs where you really want some copy-paste facility. It’s not 100% intuitive at all times, but it’s very fast to make up for it.

Features

The LACP implementation is working fine, it’s doing real dynamic LACP, you just enable it on ports and they’re bound as cables are plugged in. That also means it will not cause issues when doing kickstart installs, much different from some Linksys switches.

SNMP: You can define views, you can assign them to users / groups all no problem. V2C bulkwalks just fly (ok, the MIB is small, too). No per-VLAN counters as far as I can tell, also no sFlow, but both is hardly even found on $500 models, so that is quite fair.

Fun issue when using it with Check_MK: The interface desc’s I set from the web UI are… well… there is some encoding oopsy somewhere. The vendor supplied descriptions to the left, are all fine, but mine to the right ended up in chinese:

NTP / Syslog: All as you’d expect it. show logging buffer gives the log output locally, what else do I ask. This is one of the pieces I had to setup from the gui.

VLANs: It is possible to change the management VLAN off VLAN1 to something that is not the default vlan. Yay! Didn’t use that yet, since at home it is not … well managed ๐Ÿ™‚ ย Even GVRP is available and configurable per port in learning or other modes.

Spanning tree stuff is nicely done with STP/RSTP/MSTP support to a level where it can surely use it to extend some lab.

See the screenshot here – and they really call it a “L2 Lite Managed Switch“.

tplink SG3210 mstp settings

MSTP settings

And here’s the output from the bonding driver with working LACP:

802.3ad info
LACP rate: fast
Active Aggregator Info:
	Aggregator ID: 1
	Number of ports: 2
	Actor Key: 17
	Partner Key: zz
	Partner Mac Address: b0:48:7a:b3:xx:xx

Joining the 2nd ethernet port of my server into the bond was just a matter of adding the linux config and doing “ifup eth1” (since normal linux distros can’t do dynamic lacp grouping like a switch… go figure)

What I didn’t yet get to work was the IP ACLs that should block the config interface & snmp for non-management systems. But I guess that was just my own error.

Also nice is a bunch of DDOS protection stuff (Anyone said SYN flood?) and even ARP spoofing filters, also on a per-port level!

Stability-wise: I’ve pulled 121GBytes off a NFS share at 100+MB/s without errors. OK for me. ๐Ÿ™‚

Noise:ย It has no fan!

So this thing is taking the #1 place for best low-cost switch from the HP 1810G as of today ๐Ÿ™‚

Gentoo Vlan and Bridges for wizards


I just found a great post about networking with VLANs and Bridges on Gentoo – networking configuration had been one of the things that turned me away from there when I tried to make my Xen hosts. The author dealt with the quirks quite nicely, have a look here: Networking with Ganeti
I’ll have to revisit it when weather is bad enough again to continue work on my vlandroid!

New infiniband benchmarks – ib_rdma_bw overflow :)


Last night I was running some more benchmarks to verify the infiniband links are stable and checking if there is any negative impact if you add a 4xSDR (10Gbit) node to the other 4xDDR (20Gbit) nodes.

I was mostly looking at the rdma bandwidth with connected mode, as this is what should apply to glusterFS. I normally turned off the firewall, but I think technically it doesn’t matter with RDMA.

I noticed when changing the iterations in ib_rdma_bw to 200000 the bandwidth average displayed would drop from 2.8GB/s down to 40-50MB/s.
What had happened?
I decided to run multiple tests over all the connections (A to B, B to C, A to C, …) and found the error kept coming up once I ran a longer test than the default.

After that it was either a bug in ib_rdma_bw or my switch. I found it unlikely to be the switch, at those data rates an error should show almost immediately, like within 20GB, not after a few 100)

Turns out there was an overflow in ib_rdma_bw. Problem solved ๐Ÿ™‚

That’s a older picture of the Cisco SFS3504 switch / gateway:
Cisco SFS 3504 infiniband gateway
Right now there’s 3 infiniband cables going in and no gigabit cable coming out.
I disabled the gateway function until I know how to use infiniband partitions correcty. They’ll be mapped on ethernet VLANs so that non-IB hosts can access them via IPoIB, too. But when I just enabled this without using VLANs etc. it meant that the IB hosts would see their own and forgeign IPs twice – via IB and Ethernet. A lot of chaos resulted ๐Ÿ™‚

MNet VDSL 100


Wow,ย jetzt hab ich den Punkt erreicht, wo meine kleine VM mit dem Fileserver langsamer ist als die Internetverbindung.

Resultat: Download von Oracle Enterprise Linux mit 7MB/s und dann haengt sich down them all fuer ein paar Minuten auf, waehrend es das ISO auf den CIFS-Share ein Zimmer weiter downloads from oracle running at around 7MB/skopiert. Ey ey.