WhatsApp voice calls firewall ports

12 08 2015

Trials and errors given me following list of ports to be open in guest wi-fi firewall in order for WhatsApp calls to work.

Until then it was giving error “Call couldn’t be placed due to wi-fi network that prevents WhatsApp calls”.

TCP: 4244,5222,5223,5228,5242

UDP: 3478,45395

Making Cisco 7945G work with Asterisk again after firmware update from v.8 to v.9

24 09 2012

After SIP firmware update to version 9.3 on my Cisco 7945G and 7965G phones they all stopped to register with Asterisk. They did load config from tftp and then just stayed with “Registering” on screens forever.
What caused it is dropped UDP support in new version of SIP firmware and one required update to SEP{MAC}.xml config files, so, make following changes and may the force be with you:


SEP{MAC}.xml  (in each <line button=”N”> section):



How to set the Default Calendar permissions for all users in Exchange 2000, 2003 and 2007

12 08 2011

Configuring appropriate default calendar permissions globally in an Exchange environment can be accomplished for Exchange 2000, 2003 or 2007 with a handy tool called PFDAVadmin found here.

The Exchange 2007 commandlet Set-MailboxCalendarSettings only works for resource mailboxes and won’t accomplish what PFDAVadmin can for calendar client permissions. The only commandlet currently that mirrors this capability simply retrieves client permissions on public folders Get-PublicFolderClientPermission

With PFDAVadmin, you have two options:

  • script
  • GUI

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XenServer APC Smart-UPS shutdown and monitoring

15 04 2011

My Citrix XenServer pool is powered through network enabled APC Smart-UPS (6000 RT)

There are at least two ways of monitoring UPS state in order to shutdown pool members and VMs running in the pool when juice is over:

apcupsd (installation used to be somewhat tricky before XenServer 5.6 and included some unsupported movements)

– getting values from UPS via SNMP and acting accordingly to them – the way which I went, and you’re welcome to see detailed route description.

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transparent http proxy with Linux and Squid

11 08 2009
#<transparent proxying>
#local squid
#iptables -t nat -A PREROUTING -i $INT_IFACE -s ! $PROXY_IP -p tcp –dport 80 -j REDIRECT –to $PROXY_PORT
#remote squid
#iptables -t mangle -A PREROUTING -j ACCEPT -p tcp –dport 80 -s $PROXY_IP
#iptables -t mangle -A PREROUTING -j MARK –set-mark 3 -p tcp –dport 80
#ip rule add fwmark 3 table 2
#ip route add default via $PROXY_IP dev $INT_IFACE table 2
###!!!! do not forget to add following line to proxy_server iptables:
#iptables -A PREROUTING -t nat -i $INT_IFACE -p tcp –dport 80 -j REDIRECT –to-port $PROXY_PORT
#</transparent proxying>

if you are running Squid on or behind you Linux gateway here’s HowTo transparently run all outgoing HTTP through it

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25 05 2009

Dammit, two hours worth of log and configurations mining gave pretty unexpected results.

Not really obvious (until you find it) that on the way to fix offline address book download error 0x8004010F, you first need to make sure that error 0x80004005 is fixed. But it’s common for MS products, you know what you’re buying…

Cisco ASA 5510 and Squid via WCCP2

25 06 2008

Had this mix working smoothly for couple of years. But recent migration of proxy server to the virtualized Ubuntu server caused strange behavior – sites which are using advanced web techniques (gmail, hotmail etc.) started to show empty pages without any tracks in log files. After some research I had to shoot down TCP window scaling which is enabled by default and decrease mtu to 1400. Full configuration after the break.

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