SnmpWalk for Windows
The software can be downloaded from following website.
https://www.softpedia.com/get/Network-Tools/Misc-Networking-Tools/SnmpWalk.shtml
https://download.cnet.com/SnmpWalk/3000-2085_4-75795880.html
The software can be downloaded from following website.
https://www.softpedia.com/get/Network-Tools/Misc-Networking-Tools/SnmpWalk.shtml
https://download.cnet.com/SnmpWalk/3000-2085_4-75795880.html
Introduction to AWS Networking
AWS VPC Basics - Understanding what is VPC and Calculating CIDR for VPC and Subnets
The default network driver. Needs to map the port to host in order to access port of container.
Removes network isolation between the container and the Docker host, and uses the host's networking directly. So the containers can not have port conflicting with other containers and also host.
The IP will be the same as host.
Disables all networking for containers. Usually used in conjunction with a custom network drive.
Connect multiple Docker daemons together and enable swarm services to communicate with each other daemons.
Using this overlay network, the container on different hosts can communicate with each other.
Allow you to assign a MAC address to a container, making it appears as a physical device on the network. The Docker daemon routes traffic to container by their MAC addresses.
This allows container has different IP address on the host network.
Note: Tested using KVM network only
Let's say, you want to have a network which is different than the one ISP setup for you.
So, can you setup your own router to replace ISP route? Yes, you can, but you need to know whether you are allowed to do so by ISP. For my case, they asked me sign new agreement to say, service level drop and no technique support provided.
If you have another router, let's say RouterA
Done.
Replace RouterA with your own home build router in the simple solution.
The issue appear between 10G Qnap switch and the TPlink router. TPLink has a 2.5GB ethernet, which connects to 10G ethernet of Qnap switch. Sometimes, ping drop package, they have almost same interval!
% ping 192.168.1.254
PING 192.168.1.254 (192.168.1.254): 56 data bytes
64 bytes from 192.168.1.254: icmp_seq=0 ttl=64 time=0.464 ms
Request timeout for icmp_seq 1
64 bytes from 192.168.1.254: icmp_seq=2 ttl=64 time=0.431 ms
64 bytes from 192.168.1.254: icmp_seq=3 ttl=64 time=0.399 ms
64 bytes from 192.168.1.254: icmp_seq=4 ttl=64 time=0.302 ms
64 bytes from 192.168.1.254: icmp_seq=5 ttl=64 time=0.356 ms
64 bytes from 192.168.1.254: icmp_seq=6 ttl=64 time=0.461 ms
64 bytes from 192.168.1.254: icmp_seq=7 ttl=64 time=0.495 ms
64 bytes from 192.168.1.254: icmp_seq=8 ttl=64 time=0.450 ms
64 bytes from 192.168.1.254: icmp_seq=9 ttl=64 time=0.573 ms
64 bytes from 192.168.1.254: icmp_seq=10 ttl=64 time=0.282 ms
64 bytes from 192.168.1.254: icmp_seq=11 ttl=64 time=0.374 ms
64 bytes from 192.168.1.254: icmp_seq=12 ttl=64 time=0.604 ms
64 bytes from 192.168.1.254: icmp_seq=13 ttl=64 time=0.438 ms
64 bytes from 192.168.1.254: icmp_seq=14 ttl=64 time=0.418 ms
64 bytes from 192.168.1.254: icmp_seq=15 ttl=64 time=0.446 ms
64 bytes from 192.168.1.254: icmp_seq=16 ttl=64 time=0.570 ms
64 bytes from 192.168.1.254: icmp_seq=17 ttl=64 time=0.753 ms
64 bytes from 192.168.1.254: icmp_seq=18 ttl=64 time=0.456 ms
64 bytes from 192.168.1.254: icmp_seq=19 ttl=64 time=0.530 ms
64 bytes from 192.168.1.254: icmp_seq=20 ttl=64 time=0.531 ms
64 bytes from 192.168.1.254: icmp_seq=21 ttl=64 time=0.480 ms
64 bytes from 192.168.1.254: icmp_seq=22 ttl=64 time=0.498 ms
64 bytes from 192.168.1.254: icmp_seq=23 ttl=64 time=0.498 ms
64 bytes from 192.168.1.254: icmp_seq=24 ttl=64 time=0.465 ms
Request timeout for icmp_seq 25
64 bytes from 192.168.1.254: icmp_seq=26 ttl=64 time=0.493 ms
64 bytes from 192.168.1.254: icmp_seq=27 ttl=64 time=0.520 ms
64 bytes from 192.168.1.254: icmp_seq=28 ttl=64 time=0.462 ms
64 bytes from 192.168.1.254: icmp_seq=29 ttl=64 time=0.459 ms
64 bytes from 192.168.1.254: icmp_seq=30 ttl=64 time=0.535 ms
64 bytes from 192.168.1.254: icmp_seq=31 ttl=64 time=0.468 ms
64 bytes from 192.168.1.254: icmp_seq=32 ttl=64 time=0.505 ms
64 bytes from 192.168.1.254: icmp_seq=33 ttl=64 time=0.539 ms
64 bytes from 192.168.1.254: icmp_seq=34 ttl=64 time=0.515 ms
64 bytes from 192.168.1.254: icmp_seq=35 ttl=64 time=0.504 ms
64 bytes from 192.168.1.254: icmp_seq=36 ttl=64 time=0.519 ms
64 bytes from 192.168.1.254: icmp_seq=37 ttl=64 time=0.415 ms
64 bytes from 192.168.1.254: icmp_seq=38 ttl=64 time=0.415 ms
64 bytes from 192.168.1.254: icmp_seq=39 ttl=64 time=0.384 ms
64 bytes from 192.168.1.254: icmp_seq=40 ttl=64 time=0.443 ms
64 bytes from 192.168.1.254: icmp_seq=41 ttl=64 time=0.456 ms
64 bytes from 192.168.1.254: icmp_seq=42 ttl=64 time=0.349 ms
64 bytes from 192.168.1.254: icmp_seq=43 ttl=64 time=0.345 ms
64 bytes from 192.168.1.254: icmp_seq=44 ttl=64 time=0.272 ms
64 bytes from 192.168.1.254: icmp_seq=45 ttl=64 time=0.456 ms
64 bytes from 192.168.1.254: icmp_seq=46 ttl=64 time=0.523 ms
64 bytes from 192.168.1.254: icmp_seq=47 ttl=64 time=0.553 ms
64 bytes from 192.168.1.254: icmp_seq=48 ttl=64 time=0.389 ms
Request timeout for icmp_seq 49
64 bytes from 192.168.1.254: icmp_seq=50 ttl=64 time=0.417 ms
64 bytes from 192.168.1.254: icmp_seq=51 ttl=64 time=0.433 ms
64 bytes from 192.168.1.254: icmp_seq=52 ttl=64 time=0.467 ms
64 bytes from 192.168.1.254: icmp_seq=53 ttl=64 time=0.417 ms
^C
--- 192.168.1.254 ping statistics ---
54 packets transmitted, 51 packets received, 5.6% packet loss
round-trip min/avg/max/stddev = 0.272/0.461/0.753/0.083 ms
%
After a month, I found that in Qnap web console, the flow control on the switch port, always flicking, sometimes enable, sometimes disable. Due to this behavior, I think could be the issue with the connection between them could try to re-established again and again.
Then I disabled flow-control from switch side, because I can not find the port settings in TPlink router.
Enable flow control is to reduce packet dropping, but auto-negotiate can cause issue. Most of time both ends of ethernet can leave to auto-negotiate, but prefer to set one side manual if possible, especially two side has different highest speed.
Network disruptions are always happening, network filesystems on different OS have different behaviors.
During Synology disk migration and SSD cache reconfiguration, my Fedora 34 on iSCSI mounted NFS disk kept hanging, I checked the default NFS mount options, then found that it was using hard
option with out intr
as below,
192.168.1.10:/volume1/kvm on /kvm type nfs4 (rw,nosuid,nodev,noexec,relatime,vers=4.1,rsize=131072,wsize=131072,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=192.168.1.9,local_lock=none,addr=192.168.1.10)
I think maybe this is giving the factor of hanging.
After I changed NFS setting to soft
, I suddenly realized that my iSCSI used by Fedora OS might not able to handle interupt as well, not sure whether iSCSI got similar options.
My MacOS also got issue on samba filesystem, always disconnected after communication dropped, but my Windows machine has no such issue.
Boot from small size USB drive only holding boot partitions, rest of filesystems are on iscsi drives. Tested in EFI boot in Fedora 34.
Filesystem Size Used Avail Use% Mounted on
/dev/sdb2 428M 190M 212M 48% /boot
Filesystem Size Used Avail Use% Mounted on
/dev/sdb1 512M 31M 482M 6% /boot/efi
Define iscsi login info
GRUB_CMDLINE_LINUX="netroot=iscsi:<user>:<password>@<ip>::3260::<iqn> rd.iscsi.initiator=<client iqn> rhgb quiet ...
Define network interface with static ip 192.168.1.2
, gateway 192.168.1.254
, nameserver 192.168.1.1
, interface enp0s10
.
ip=192.168.1.2::192.168.1.254:255.255.255.0::enp0s10:off nameserver=192.168.1.1
Define network with bridge interface br0
on network interface enp0s10
ip=192.168.1.2::192.168.1.254:255.255.255.0::br0:off nameserver=192.168.1.1 ifname=enp0s10:xx:xx:xx:xx:xx:xx bridge=br0:enp0s10"
Update grub using following command
grub2-mkconfig -o /boot/grub2/grub.cfg