When your DHCP client has lease renewal issues, Sendmail may be at fault

On one of our VPS instances, I noticed some seriously erratic behavior with the DHCP client taking a long time to renew its leases when the machine was booting up, or failing to renew at all.

It took some time before I noticed this output from dhclient:

/sbin/dhclient-script: 28: .: Can't open /usr/share/sendmail/dynamic

This didn’t make any sense as we never have and never will install sendmail on any VPS. So using apt, I was able to see that one or more of the sendmail packages had “incomplete” status (displayed as ‘c’ in aptitude if you’re using that), i.e. it was not installed but some configuration files remain. After purging those packages, dhclient had no problems whatsoever in renewing the leases.

Who knew sendmail could even trash DHCP ūüôā

 

 

IP-Only, NOC, customer service, support, and network loops

IP-Only often boasts about being “the man” when it comes to Swedish Internet infrastructure and their competence in networks. Customer service and fast response to serious network issues such as routing loops seems to be of … less importance to IP-Only. It’s fascinating how “big players” so often seem to ignore “small customers”. We reported this network issue to IP-Only on 13-Jun-2016 (Monday). On 17-Jun-2016 (Friday), they still don’t know what the problem is. But they are “investigating it”. In the meantime, there is zero response from them until you start screaming.

It’s so comforting to know we’re in safe hands with them, being “the man” when it comes to the Internet infrastructure in Sweden.

What’s less comforting is that they don’t seem to monitor their network equipment nor know how it works.

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