Devuan4/Debian11 usability annoyances

Problem: When pasting commandos to the shell, the shell no longer executes the command but shows the pasted text highlighted and shows the line feed but does not process it. Discussion: Devuan4 and Debian11 upgraded the readline library with a new default “feature” that should prevent noobs from accidentally pasting commands into the shell. But …

Continue reading ‘Devuan4/Debian11 usability annoyances’ »

Cisco Serial Number Production Date

Every Cisco switch has a serial number that shows information about it’s production location and year. As you see this switch is very old and was running very long. Without any issues btw. The serial number here is shown as “Processor board ID”, you might also find “System serial number” or similar. The format is …

Continue reading ‘Cisco Serial Number Production Date’ »

Linux Connection NAT Helper not Working

Some protocols need more than one TCP or UDP connection. For NAT to work the firewall needs to open additional ports to allow client server connection automatically. Examples are FTP (port 21 handshake, additional ports for data), PPTP (port 1723 for handshake, proto GRE 47 for payload) Since Linux kernel (~) 4.7 these helpers are …

Continue reading ‘Linux Connection NAT Helper not Working’ »

Debian Curl/PHP/wget etc show an certificate error falsely

Problem: curl php wget and others show a cert error like the following since 6. Oct 2021, even though the cert has not expired: The asked server uses a Letsencrypt certificate. Discussion: Currently Letsencrypt includes two chains for validation of the certificate: Cert -> R3 -> ISRG Root X1 (in new trust store) Cert -> …

Continue reading ‘Debian Curl/PHP/wget etc show an certificate error falsely’ »

Devuan / Debian Versions

Admins who prefer a Unix style operation systems and don’t like the centralized “one tool doing it all” approach of systemd, switch to Devuan. This mostly improves uptime over boot time. Admins of servers don’t care about boot time and prefer uptime. This list keeps track of the related versions of Devuan and Debian. Debian …

Continue reading ‘Devuan / Debian Versions’ »

Cisco ASR-1001-X Update

There are at least two pieces of software you can update in a Cisco ASR-1001-X. The ROMMON (firmware) and the IOS itself. This router uses “Cisco IOS XE Software”. Which is an IOS process on a Linux kernel as far as I know. Cisco recommends specific ROMMON releases for different generations of software. You can …

Continue reading ‘Cisco ASR-1001-X Update’ »

LS Style After Devuan 3 or Debian 10 Update

After Devuan 3 update ls output showed characters, that are not really in the directory listing. The reason is that “ls” draws quotes around filenames with spaces. This is a bug from my point of view, ls should never change the actual filenames. If a filename has quotes or double quotes it’s even weirder . …

Continue reading ‘LS Style After Devuan 3 or Debian 10 Update’ »

Time Format after Devuan 3 and Debian 10 Update

After updating to Devuan 3 the date command shows 12hours am/pm but my days have 24 hours. The locale was always en_US.UTF8 to keep sane command and error output. Debian 10 thinks they had to fix the correct hour display to the complicated one. Therefor all sysadmins like me have to apply the following workaround, …

Continue reading ‘Time Format after Devuan 3 and Debian 10 Update’ »

Mikrotik OSPF Routing Distance Ignored

Discussion: Every routing protocol has a default distance to help the router to decide which route to use in case of multiple routes for the same destination. For Mikrotik routers these distances are listed here:https://wiki.mikrotik.com/wiki/Manual:Route_Selection_Algorithm_in_RouterOSIf you want to configure a backup link that is only activated when the OSPF main route is missing, you can …

Continue reading ‘Mikrotik OSPF Routing Distance Ignored’ »