Configure source ip for serveral services e.g. tacacs, logging, ntp

[Joe Stonke]

Hello,

my equipment is used behind a firewall. Therefore i've to enable all the specific traffic for management through the firewall.

How can i define the source IP address of all responses or logging services?

I would like to define all requests e.g. caused by tacacs or logging are coming from a defined interface. For the following services i would like to define a source IP:
- Tacacs
- Logging
- NTP
- telnet
- SSH
- TFTP / FTP
- DNS query

Would be great, if you could give me the command for it.

Thank you all for your support in advance.

[Pieter 't Hart]

im not sure, but i don't think there really is a single command to do that.

Normally the address of the "primary vlan" (default vlan-1) will be preferred for those packets.

But it's possible that the adress of the first interface that's "up" will be used.
If at some time this is not the primary vlan an other address may get selected.

You can control this by configuring a "loopback interface".
This loopback interface is the first interface to come "up" (as it needs no "link" to come up first).
And will subseqently be used as source address, if not otherwise configured for a service.