microdevsys

[microdevsys]

Unable to ping NLB Gateway from outside the NLB subnet or different subnets

Unable to ping NLB Gateway from outside the NLB subnet or different subnets.  Getting timeouts when attempting to do so? # nc -vz 192.168.0.224 Ncat: Version 7.50 ( https://nmap.org/ncat ) Ncat: Connection timed out. While host is on a subnet external to the NLB subnet? # ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback…

[microdevsys]

Filter Duplicate or DUP traffic in ICMP Ping requests 64 bytes from 192.168.0.100: icmp_seq ttl time ms (DUP!) from NLB Network Load Balancing Clusters

Getting this? -bash-4.2$ ping 192.168.0.224 PING 192.168.0.224 (192.168.0.224) 56(84) bytes of data. 64 bytes from 192.168.0.224: icmp_seq=1 ttl=127 time=0.860 ms 64 bytes from 192.168.0.224: icmp_seq=1 ttl=127 time=1.22 ms (DUP!) 64 bytes from 192.168.0.224: icmp_seq=2 ttl=127 time=0.622 ms 64 bytes from 192.168.0.224: icmp_seq=2 ttl=127 time=0.872 ms (DUP!) Apparently this can cause issues on…

[microdevsys]

Stop and start WAN or LAN interfaces on DD-WRT

Stop WAN or LAN ip link set vlan2 down To bring things back up: ip link set vlan2 up Command for WAN in this case: udhcpc -i vlan2 -p /var/run/udhcpc.pid -s /tmp/udhcpc -O routes -O msstaticroutes -O staticroutes -x hostname:DD-WRT-HEIMDALL NOTE: Change the ‘hostname’ to the hostname that’s set in the UI. Enjoy!

[microdevsys]

Converting a Integer to Binary

Let’s take a number: 78 and convert it to binary.  We know an 8 bit number is between 0 and 255, let’s draw this out and use 0’s initially, where the top row represents the integer equivalent: POS 1 2 3 4 5 6 7 8 INT 128 64 32 16 8 4 2 1 ———————————————————- BIN 0 0 0 0 0 0 0 0 Let’s convert 78 to decimal now: 78 | 0100 0000 | 78 – “64” = 14 78 | 0100 1000 | 14 – “8”  = 6 78 | 0100 1100 | 6…

[microdevsys]

VCSA InvalidCredentialsException: Solution user cert is not valid

vmware-hvc vmware-imagebuilder vmware-content-library vmware-sps # Took VERY long to start. vmware-statsmonitor vmware-updatemgr vmware-vapi-endpoint vmware-vpxd vmware-vcha # Not automatic vmware-vpxd vmware-vpxd-svcs vmware-vsan-health vstats wcp ——- ==> sso/vmware-identity-sts.log <== 2024-09-19T20:01:51.383Z INFO sts[81:tomcat-http–43] [CorId=e624494b-aa1a-432c-a2fb-9dbd8d59d5a4]…

[microdevsys]

Recently ran into this lovely message: root@g73sw01:~# root@g73sw01:~# systemctl status gdm3 -l ? gdm.service – GNOME Display Manager Loaded: loaded (/usr/lib/systemd/system/gdm.service; static) Active: active (running) since Sat 2024-09-14 14:42:24 EDT; 1 day 21h ago Main PID: 3254 (gdm3) Tasks: 4 (limit: 19063) Memory: 5.7M (peak: 50.2M) CPU: 2.239s CGroup: /system.slice/gdm.service ??3254…

[microdevsys]

SSSD krb5_child Disk quota exceeded

Getting this? Sep 14 14:04:08 g73sw01.nix.mds.xyz krb5_child[53814]: Disk quota exceeded Digging further: root@g73sw01:~# cat /proc/key-users 0: 163 162/162 131/1000000 2746/25000000 101: 1 1/1 1/200 9/64000 108: 1 1/1 1/200 9/64000 110: 4 4/4 4/200 44/64000 113: 2 2/2 2/200 18/64000 123: 1 1/1 1/200 9/64000 128: 4 4/4 4/200 44/64000 135: 1 1/1 1/200 9/64000 137: 1 1/1 1/200 9/64000 997: 1 1/1…

[microdevsys]

Mount Samba Share on Ubuntu

Getting this? root@g73sw01:~# mount -t cifs -o credentials=/home/tom/.smbcredentials,vers=3.0 //nfs-c01.nix.mds.xyz/nfs-vincent ./test -vv mount: /root/test: mount(2) system call failed: No route to host. root@g73sw01:~# Solve it with: root@g73sw01:~# apt-get install keyutils cifs-utils Cheers, HTH

[microdevsys]

Identifying Ubuntu NVMe Drives based on Bus Number

There are three NVMe’s in a laptop. Two of the NVMe’s are the exact same model, Intel, and the other is a Kingston NVMe. All NVMe’s are 512GB. All are running either Windows 11 on the two identical drives, or Windows 10 on the Kingston drive. I want to keep only the second NVMe drive with Windows 11, and overwrite the first NVMe one, with Ubuntu. However, when Ubuntu installation starts up, the…

[microdevsys]

Ubuntu Disable RST while Windows Partitions Exist

Windows 11 already has the AHCI drivers by default.  There’s a number of articles that explain how to modify regex settings.  Usually this is not for the average user, or even an experienced one since if it doesn’t work, those settings would need to be reverted.   And there may not be an easy way to do this once the system can’t boot up, esp since windows will take actions, modifying files,  to…

[microdevsys]

Ubuntu: network unclaimed error

Getting a: network unclaimed error after a recent NVIDIA or apt update command? After a recent upgrade, system wouldn’t boot to a UI.  Blank screen is shown.  To solve this, hit SHIFT + F2 at the blank screen, to switch to a terminal login screen.  Once at the login screen, change directory to /lib/modules/: cd /lib/modules/ and type: ls -altri You may see that the kernel version has been…

[microdevsys]

OpenVPN Setup on Ubuntu

To get the latest version of OpenVPN, which will be 2.6 since files for 3.0 are still not yet available at the time of this article, we first need to import the OpenVPN repository key: # ls -altri /etc/apt/keyrings/ # curl -fsSL https://swupdate.openvpn.net/repos/repo-public.gpg | gpg –dearmor > /etc/apt/keyrings/openvpn-repo-pub-key.gpg Change ‘arch’ to match your CPU architecture. Check the…

[microdevsys]

IPA Fails to start: Timeout Exceeded and No Route to Host when IPV6 disabled

IPA doesn’t start? Just prints the following when an attempt is made to start it? # strace -f -s 256 ipactl start . . . . socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 4 connect(4, {sa_family=AF_INET, sin_port=htons(389), sin_addr=inet_addr(“127.0.0.1”)}, 16) = 0 getsockname(4, {sa_family=AF_INET, sin_port=htons(51027), sin_addr=inet_addr(“127.0.0.1”)}, [28->16]) = 0 close(4) =…

[microdevsys]

Find Which Device Connected to a Cisco Switch Port

Issue the following: mdscisco07#sh mac address-table interface gigabitEthernet 1/19 Unicast Entries vlan mac address type protocols port ——-+—————+——–+———————+——————– 5 abcd.1234.wxyz dynamic ip,ipx GigabitEthernet1/19 HTH

[microdevsys]

Configuring an Ubuntu Workstation with XRDP, SSHD, VNC, FreeIPA, SSSD, Java, NetBeans

Building an Ubuntu Workstation for development and general use, one that can be accessed remotely with central authentication.  Most of the commands below will be ran as the root user, hence # sudo su – to root will be needed.  Let’s get going: ALIAS SETUP Personally, the following alias just makes it a tad easier to get around: $ grep -Ei altri ~/.bashrc alias lt=’ls -altri’ $ Some of the other…

[microdevsys]

HAproxy Configuration to AD Active Directory Servers

Quick configuration to proxy AD requests through another server. Set the following on the proxy server. Note the frontend server is on port 443 whereas the backend server is on port 389: # vi /etc/haproxy18/haproxy.cfg global log 127.0.0.1 local0 debug stats socket /var/run/haproxy.sock mode 0600 level admin # stats socket /var/lib/haproxy/stats maxconn 4000 user haproxy group…

[microdevsys]

klist: Improper format of Kerberos configuration file while initializing krb5

There were extra spaces or space with a different font, in front of “” that got copied over from an editor.  Once replaced, everything worked fine: root@g73sw01:/etc# klist -kte klist: Improper format of Kerberos configuration file while initializing krb5 root@g73sw01:/etc# vi /etc/krb5.conf root@g73sw01:/etc# klist -kte Keytab name: FILE:/etc/krb5.keytab KVNO Timestamp Principal —- ——————-…