Salut Mihai, any decent monitoring tool should be able to achieve what you need: PRTG(btw. they just released an alpha linux probe)100 Sensors free https://kb.paessler.com/en/topic/25313-sensor-for-bgp-statusZabbix https://share.zabbix.com/network_devices/cisco/cisco-bgp-ipv4-ipv6-32-bit-as... ,etc. Most have some sort of templates, some with custom options. If you don't want/need the overhead of such an tool you can just build a ba(sh) or python parsing script that does some snmpwalk or ssh 'expect' commands and in the end send email or curl post. ;)
Beste Grüsse, Regards si s-auzim de bine Florin Sfetea