Jak resetovat SMC vašeho Macu

https://support.apple.com/cs-cz/HT201295

macOS – SSH Error ‘No Matching Exchange Method Found’

Davids-MacBook-Pro:~ dpasek$ ssh admin@192.168.4.253
Unable to negotiate with 192.168.4.253 port 22: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1,

Solution ...
https://www.petenetlive.com/KB/Article/0001245

Solution

This is not Apple’s fault, it’s OpenSSH version 7. SHA1 is weak, so support for it has been removed. Which is fine, but all my clients Cisco Firewalls/Routers/Switches are probably all using  RSA/SHA1. So until they re all updated I’m going to need to re-enable SHA1.

Open a terminal windows and execute the following;

sudo nano /etc/ssh/ssh_config
ENTER YOUR PASSWORD

Locate the line ‘ #   MACs hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160′ and remove the Hash/Pound sight from the beginning.

Locate the line ‘ #   Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc’ and remove the Hash/Pound sight from the beginning.

Then paste the following on the end;

HostkeyAlgorithms ssh-dss,ssh-rsa

KexAlgorithms +diffie-hellman-group1-sha1

VMware Cloud Foundation - Overview

Overview

1. VCF lze postavit ve dvou deployment modelech
1. Standardní – to je jedna Management domain (minimum 4 hosty, maximum 64) + až 15 oddělených Workload domains (minimum 3 hosty per pro každou, maximum 64).

V tomto modelu je tedy potřeba mimimálně 7 hostů (4 + 3), oddělení workloadu ja na úrovni samotných hostů.

2. Konsolidovaný -  Management a Workload domains je společná, minimální počet jsou 4 hosty a lze rozšiřovat až na 64 hostů.

Oddělení workloadu je v tomto modelu na úrovni Resource pool-ů.

Tento model nepodporuje automatický deployment VMware Enterprise PKS a VMware Horizon.

V budoucnu lze přejít z konsolidovaného modelu na standardní.

2. vCenter
1. Licence vCenter není součástí balíku VCF a je potřeba zajistit samostatně
2. Pro VCF je potřeba jedna licence vCenter (platí pro oba deployment modely).

V případě Standardního modelu je součástí každé Workload domain vlastní instance vCenter serveru (ty se ale nelicencují, opět stačí jedna licence).

3. Není podporováno použití existujícího/externího vCenter serveru.

3. Hardware
1. Management domain případně Konsolidovaný model musí mít pod sebou vSAN. Ve Standardním modelu jsou pro Workload domény podporovány i externí storage (NFS, FC SAN).
2. Do verze VCF 3.9.1 bylo možné pro komunikaci mezi hosty (management, vSAN, vMotion) vyžít pouze dvě fyzické NIC, od verze 3.9.1 je možné použít až 4 pNICs, pokud je použito NSX-V nebo až 6 pNICs, pokud je použito NSX-T. 

4. Networking
1. Management domain a obecně konsolidovaný model podporuje pouze NSX-V
2. Do Workload domain lze zvolit zda bude použito NSX-V nebo NSX-T
3. VCF od verze 4.0 by měl podporovat již pouze NSX-T (Přechod z NSX-V by měl být vyřešen při upgrade)

Windows 10 - ICMP Allow incoming V4 echo request

Command

netsh advfirewall firewall add rule name="ICMP Allow incoming V4 echo request" protocol=icmpv4:8,any dir=in action=allow

Source: https://www.howtogeek.com/howto/windows-vista/allow-pings-icmp-echo-request-through-your-windows-vista-firewall/

Alternativ way over GUI

Windows Firewall
Search for Windows Firewall, and click to open it.
Click Advanced Settings on the left.
From the left pane of the resulting window, click Inbound Rules.
In the right pane, find the rules titled File and Printer Sharing (Echo Request - ICMPv4-In).
Right-click each rule and choose Enable Rule.

Source: https://kb.iu.edu/d/aopy

How to Use Netcat Commands

Sources:

• https://www.varonis.com/blog/netcat-commands/
• https://www.unixfu.ch/use-netcat-instead-of-telnet/

root@flxb-node-01:~ # nc -z -v www.google.com 80
Connection to www.google.com 80 port [tcp/http] succeeded!

root@flxb-node-01:~ # nc -z -v www.google.com 443
Connection to www.google.com 443 port [tcp/https] succeeded!

Clone Nested ESXi

The easiest and cleaner way after the clone, is to completely reset ESXi system configurations

I find the "reset system configuration" in DCUI very useful for this task.
There is also a way to perform this task via SSH:

#  /sbin/firmwareConfig.sh --reset   (this will automatically reboot your host)
# /sbin/firmwareConfig.sh --reset-only (this will not reboot host and needs to be done manually)


However, if you do not want to start from scratch you can tweek cloned system. The process is inspired by https://www.virtuallyghetto.com/2013/12/how-to-properly-clone-nested-esxi-vm.html

# to inherit vmknic MAC addresses from hardware NICs (actually vNICs)

esxcli system settings advanced set -o /Net/FollowHardwareMac -i 1

#verification
esxcli system settings advanced list -o /Net/FollowHardwareMac

# change IP settings and DNS hostname
Do it in DCUI

# reset ESXi UUID

sed -i 's/system\/uuid.*//' /etc/vmware/esx.conf
reboot

# Verification of ESXi UUID - esxcli
esxcli system uuid get

# Verification of ESXi UUIDs for all ESXi hosts within vCenter - powercli
Get-VMHost | Select Name,@{N='ESXi System UUid';E={(Get-Esxcli -VMHost $_).system.uuid.get()}}

# if the ESXi host was cloned from the ESXi host already connected to vCenter reset VPXA config

edit file /etc/vmware/vpxa/vpxa.cfg
locate section <vpxa></vpxa> and delete all content inside

reboot

# just in case local datastore was cloned along with ESXi

esxcli storage vmfs snapshot resignature -l datastore1


# NOTE: to have nested vSAN on native vSAN, you have to add following settings into your physical vSAN nodes
esxcli system settings advanced set -o /VSAN/FakeSCSIReservations -i 1


UNDERLINE INFO

# Historicky se pry pouzivala tato nastaveni

esxcli system settings advanced set -o /VMFS3/HardwareAcceleratedLocking -i 1
esxcli system settings advanced set -o /LSOM/VSANDeviceMonitoring -i 0
esxcli system settings advanced set -o /LSOM/lsomSlowDeviceUnmount -i 0
esxcli system settings advanced set -o /VSAN/SwapThickProvisionDisabled -i 1
esxcli system settings advanced set -o /VSAN/FakeSCSIReservations -i 1

esxcli system settings advanced list -o /VMFS3/HardwareAcceleratedLocking
esxcli system settings advanced list -o /LSOM/VSANDeviceMonitoring
esxcli system settings advanced list -o /LSOM/lsomSlowDeviceUnmount
esxcli system settings advanced list -o /VSAN/SwapThickProvisionDisabled
esxcli system settings advanced list -o /VSAN/FakeSCSIReservations

# Default hodnoty jsou
esxcli system settings advanced set -o /VMFS3/HardwareAcceleratedLocking -i 1
esxcli system settings advanced set -o /LSOM/VSANDeviceMonitoring -i 1
esxcli system settings advanced set -o /LSOM/lsomSlowDeviceUnmount -i 1
esxcli system settings advanced set -o /VSAN/SwapThickProvisionDisabled -i 1
esxcli system settings advanced set -o /VSAN/FakeSCSIReservations -i 1

2-Node vSAN design and performance test

2-node vSAN
capacity planning
sizing
performance

ESXi Logical Specification

ESXi Logical Specification

vSAN Logical Design

vSAN Logical Design

Results of performance tests generated by IOmeter

Results of performance tests