Pc

if you read my previous pieces about my home network, you know well my core switch is Nexus 93180YC-EX. you know… home, core switch. anycasted services at any point in time I have a number of DNS (and DHCP) servers available, all reachable via either 192.168.168.168 or 2001:470:xx:a6::168. no matter what is going on, at least one should be able to respond. currently, in the “cluster” I have two VMs and two physical Raspberry Pi 4B+. all of them run on FreeBSD 14.0-STABLE, with nsd, unbound and bird packages, last one to do the advertisement of IPv4 and IPv6 addresses. ...

if, like me, you would like to use RbPi 5 and FreeBSD at the same time, simply copying the 13.2/14.0 image to the SD card is not enough. in addition to the already known one (where rdiskX contains the ID of your SD card/USB key - beware of accidentally overwriting your system drive or another data drive): $ xz -dc FreeBSD-14.0-RELEASE-arm64-aarch64-RPI.img.xz | sudo dd of=/dev/rdiskX status=progress bs=64M 5368709120 bytes (5369 MB, 5120 MiB) transferred 261.187s, 21 MB/s 320+0 records in 320+0 records out 5368709120 bytes transferred in 261.198115 secs (20554165 bytes/sec) ...

ever since the initial tuning of the FreeBSD TCP/IP stack around version 4.x, I’ve found myself occasionally tinkering with the contents of /etc/sysctl.conf just to fine-tune things, you know over time, numerous changes have been made to the FreeBSD TCP/IP stack, including the introduction of modularity. however, MacOS X, being based on FreeBSD, is more conservative and lacks certain options. therefore, on my MacOS systems, I make use of the following /etc/sysctl.conf configuration: ...

recently during casual browsing of WLAN controller i spotted that sometimes users are having problems with receiving responses from DHCP server. i was suprised, as family doesn’t complain - and they’d do that immediately. well, so i went troubleshooting element by element. obviously, switches were primary suspect. why? everything was working, and those DHCP problems were very, very rare - that may mean drops on switch interfaces. Cisco QoS configuration on Catalyst and Nexus switches is far from easy. comparing this however to other vendors… there’s really nothing to compare. on one side you can do whatever you want, on the other side - you can shoot yourself in both foots, stomach and then in the head pretty quickly. just assume, that if you haven’t spent couple of weeks labbing QoS on real hardware - it’s area that you shouldn’t wander alone in unsupervised ;) in very simple terms, either use dedicated GUI for managing campus networks - Cisco DNA Center or stop at either enabling QoS globally (mls qos) or disabling it (no mls qos). ...

my 256GB SSD drive in MacPro 2013 started to fill up recently. i went on short googling to see how to extend it without relying on NAS of course. and i get nice offer. it seems that good people in the internet found a way to interface typical NVMe disk drives with the socket Apple uses. and so i became user of 1TB Samsung SSD drive. that upgrade gave me also speed bump - on encrypted drive transfers shoot up from 500MBbs (reading) and 380MBbs (writing) to 1.3GBps for both reading and writing (disk itself can do 2.5Gbps but PCIe bus in MacPro is limiting factor here). ...

during the last 30 years, processor speeds has increased from millions of cycles to billions - multiplied by multi-core and special mechanisms that increase the efficiency of working with ‘boring’ cores. Pentium 66 processor from 1993 contained 3.2 million transistors, which is anyway quite a value, considering they are packed into a space comparable to that of four dices - and contains one main unit. available today Xeon E5-2699v4 has 22 cores operating at nominal frequency 2.2GHz clock and 7.2 billion transistors. ‘imagine that’! ...

failure that Tidal came to be and at the same time success to which Apple Watch is experiencing (the same that has trouble keeping it’s bettery up for ONE day) is troubling. on one side we have market, that is able to verify this poor and blatant run for money organized by multi-billionaires, obviously coupled with lack of any style and market research (which would show there are other, better, faster and with wider selection of artists and capabilities services available already), on the other hand - Apple Watch? really? ...

quite recently i described my own new workstation. it has dual Xeon processors, and today i decided to upgrade memory from 128GB to 256GB (yeah, i use to run a lot of VMs). so below you can see the outcome - 256GB RAM, 2 physical CPUs, 16 cores, 32 threads: great advantage of having such beast at your disposal is that you simply can run everything thrown at it. it’s quiet, it’s effective and it also doubles as great gaming station. on the other side, i’m constantly asking myself a question - “which part of ocean i’m warming up right now?”. ...

…workstation requires two! ;) i had some time over Christmas to finally build myself following beast: Asus Z9PE-D8 WS (BIOS 5304, original 3304 had some interesting bugs Xeon E5 2660 (Sandy Bridge EP/EX) - 16 cores, 32 HT Corsair H80i for CPU cooling 64GB RAMu (8x 8GB DDR3 1600 ECC) OWC 480GB PCIe - has two 240GB blades in RAID0 Corsair Obsidian 900D 2x Seagate 4TB HDD [6x Samsung 2TB] LSI 9261-8i to drive those mechanical disks in RAID5 Creative SB ZX AMD Radeon 7970 connected to three Dell U2412 monitors Intel x520 NIC connected to Catalyst 2960S and to other workstation - Xeon 5670, 48GB RAMu, OWC 240GB as boot and two 2TB RAID0 disks as RAID0 for ESXi 5.5 as we sometimes laugh with each other - ‘it opens Total Commander pretty bloody fast’. VMware Workstation 10 orchestrates number of VMs running at the same time and i can still use workstation as normal desktop. Visual Studio 2013 is able to compile whole projects in a blink of an eye. ...

don’t start your php upgrade at 2:40 in the morning. as you’ll stay awake until 5am :)