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Below is a guide to the main areas and features that you should be aware of to ensure that your Cisco Catalyst switch is fully secured within your network. 1. PASSWORDS First of all passwords are configured. One password is used for the enable password and the other will later be assigned to the console … Read more
When compiling from source you may see the following errors occur : /usr/include/sys/siginfo.h:259: error: parse error before “ctid_t” /usr/include/sys/siginfo.h:292: error: parse error before ‘}’ token /usr/include/sys/siginfo.h:294: error: parse error before ‘}’ token /usr/include/sys/siginfo.h:390: error: parse error before “ctid_t” /usr/include/sys/siginfo.h:392: error: conflicting types for `__proc’ /usr/include/sys/siginfo.h:261: error: previous declaration of `__proc’ /usr/include/sys/siginfo.h:398: error: conflicting … Read more
When compiling programs in Solaris you may find you recieve the following error (or something along the same lines) complaining about grep. checking for grep that handles long lines and -e… ./configure: line 3859: 13085 Killed “$ac_path_GREP” -e ‘GREP$’ -e ‘-(cannot match)-‘ <“conftest.nl” >”conftest.out” 2>/dev/null ./configure: line 3859: 13092 Killed “$ac_path_GREP” -e ‘GREP$’ -e ‘-(cannot … Read more
Reflective access-lists allows the router to pass “established” tcp traffic that has been previously allowed via another ACL. Due to routers to not having (by default) a state table, this ensures that you do not have to create additional access list entries to allow the return traffic of a permitted tcp session. (config)# ip access-list … Read more
In a worst case scenario someone could gain access to your router, clear the boot image and config. This would result in a lengthy down time and a lot stress. Cisco have tried to address this but the use of the following commands which prevents the clearing of your config and boot image (config) # … Read more
When trying to install the gcc package on Solaris you may find you get the following error : cpio: Cannot write “reloc/lib/gcc-lib/i386-pc-solaris2.10/3.3.2/cc1obj”, errno 28, No space left on device cpio: Cannot write “reloc/lib/gcc-lib/i386-pc-solaris2.10/3.3.2/cc1plus”, errno 28, No space left on device cpio: Cannot write “reloc/lib/gcc-lib/i386-pc-solaris2.10/3.3.2/collect2”, errno 28, No space left on device cpio: Cannot write “reloc/lib/gcc-lib/i386-pc-solaris2.10/3.3.2/f771”, … Read more
Below shows a number of commands that you can use for securing your Cisco router. Block Denied Logins – Useful for delaying denied logins when someone is trying to brute force your router. (config)# login block-for [seconds] attempts [attempts] within [seconds] Quiet Login – Allows you to still login once the router has blocked login … Read more
CLI Views allow your to to create sub administrator within your Cisco device. This can also be thought of as an extension to privilege levels, giving you further granularity over what your users are allowed to do. Creating views Below shows you the commands required to create a view mode. In all the examples we … Read more
TACACS+ (Terminal Access Controller Access-Control System Plus) is a Cisco proprietary protocol which provides access control for routers, network access servers and other networked computing devices via one or more centralized servers. TACACS+ uses port tcp 49 and provides separate authentication, authorization and accounting services. Below shows you the general steps involved, First of all … Read more